If a project goes into production after requirements gathering, and no one has taken the time to painstakingly document every decision, exception, specification, and assumption, were the project requirements really gathered?
The importance of requirements gathering is often underestimated on multiple levels. When budgets are thin, timelines are tight, and scope is creeping, requirements documentation tends to be the first deliverable to go and the last deliverable to be considered. This is surprising, especially when you consider that disregarding a thorough requirements gathering process means sacrificing a sound point of reference for checks and balances throughout production and QA, jeopardizing expectations between the client, your team, and the end users, and leaving plenty of room for error and ambiguity. All of this can very quickly eat into your margins (and your sanity).
At first glance, the requirements gathering process and requirements documentation can seem intimidating—but it doesn’t have to be. I’m going to shed some light on the importance of requirements, the process of requirements management and gathering, some techniques to consider, and approaches to writing requirements documentation. While requirements documentation may get complicated, the process doesn’t have to be. My goal with this article is to provide you a simplified, intuitive approach to requirements gathering and documentation.
Topics In This Article
This is a complete guide with lots of useful information. You can jump straight to these sections to touch on the specifics:
- What Are The Two Types Of Requirements?
- The Importance Of Requirements Management
- Requirement Example
- Requirements Management Tools
- Requirements Gathering Process
- The Wrong Way To Gather Requirements
- Requirements Gathering Techniques
- Expert Tips On How To Write A Requirements Document
- Project Requirements Document Template
What Are Requirements?
Starting with a basic requirement definition, requirements in digital can be categorized into two types: functional and non-functional.
For the purposes of this discussion, we’ll focus on these two types of requirements that we usually see in digital products and services. Of course, there are other types, such as legal and technical requirements, and depending on the context, the person in charge of handling requirements documentation may need additional training in technical writing, information mapping, and more.
What Are Functional Requirements?
For a digital engagement, functional requirements relate to a product’s functionality: its capabilities, usability, features, and operations as they relate to the intended purpose of the product. Often, functional requirements are clearly referenced as such in Functional Requirements Documentation (FRD). While a Statement of Work (SOW) outlines the high-level goals and requirements of the desired product, an FRD provides a more in-depth elaboration of these requirements, which are gathered as soon as a project kicks off and up until a project begins production.
Side note: requirements are not limited to the window of time before production: change order documentation, warranty documentation, etc. are useful forms of ongoing requirements documentation that occurs throughout a project—or even beyond the project! For as long as you work with a client, the documentation is ever-growing and ever-evolving.
Depending on the size and scope of a project, you might decide on a milestone between the SOW and FRD (as this timeframe can span for months). In this case, some teams create Business Requirements Documentation (BRD) to provide a formal midway sign-off—an expectation checkpoint—for all parties. This presents the opportunity for the Project Manager to confirm the team is heading in the right direction before getting too far down the road with deliverables.
What Are Non-Functional Requirements?
Non-functional requirements encompass anything not related to a product’s functionality: its performance, stability, security, and technical specifications, to name just a few types of non-functional requirements in the digital industry.
Functional vs. Non-Functional Requirement Examples
Both functional and non-functional requirements documentation are equally instrumental in their own ways. They exist hand in hand; one is directly affected by the other.
Even so, not all non-functional requirements correspond directly to a functional requirement. Server setup and configuration, for example, is a non-functional requirement that has an impact on an entire site’s stability, without a direct 1:1 relationship with any singular functional requirement.
Here are a few examples of functional and non-functional requirements, and how they are related:
- Functional Requirement: payment processing functionality
- Non-Functional Requirement: SSL certificate
While it’s 2018 and websites should have SSL certificates regardless, it’s especially important to do so if there is payment processing functionality implemented on the site. This is an example of a non-functional requirement (SSL certificate, an element of the implementation which affects security) directly affecting a functional requirements (payment, an element of the implementation which affects usability).
Here’s another example:
- Functional Requirement: tools and resources (PDF, infographics, courseware, spreadsheets) available for users, accessible via the Resources landing page
- Non-Functional Requirement: administrative panel file format specs (e.g. “The following file formats are valid for upload within the administrative user panel, in relation to the Resources page: .zip, .jpeg, .csv, .pdf”)
Per the functionality of the Resources landing page, users are able to access resources such as PDFs, infographics, courseware, or spreadsheets. This functionality is a feature and an operation of the page. It is a functional requirement.
The administrative panel file format specs, on the other hand, are a non-functional requirement; they are technical specs related to administrative functionality. They do not affect the usability of the end users. Yes, these specs do affect the usability of the administrative users, but it does not directly define what the product’s functionality is for the end user. This is a non-functional requirement.
The Importance Of Requirements Management
Requirements management is important for two main reasons:
- Requirements documentation serves as a point of reference to document the evolution of a project, its moving parts, and its implementation
- Requirements documentation serves as a blueprint for the client to better understand what to expect out of the project (the what, where, when, and why of the project).
In addition to outlining what they can expect, part of requirements management planning should outline what not to expect. Including an “Assumptions” and/or “Exclusions” section is a wise approach to eliminate the risk of the dreaded client imagination.
Let’s look at an example showing how requirements gathering is important as a point of reference and a blueprint for managing expectations:
- What: PayPal integration
- Where: Checkout
- When: Within step 3 of 4 in the checkout experience (after the shipping address webform, before confirmation)
- Why: An established integration (e.g. PayPal) is a better solution than a robust custom build integration for a payment service in this case because it easily meets client requirements.
- Flat fee for all shipping & handling
- All shipping is within the U.S. (not including Alaska or Hawaii)
- Taxes do not apply
- Custom shipping & handling fee calculations
- Shipping internationally, to Alaska, or to Hawaii
- Tax rules
Remember: the smaller the delta between client expectation and reality with their digital product, the happier your client is going to be with the end result.
The quality of your requirements management directly correlates with your ability as a Digital Project Manager to reduce “gray area” for client expectations.
A vast majority of the time, a client will be receptive to your limiting scope creep if it means you’re preserving their budget; if you educate the client sufficiently on why a feature will be addressed (or not addressed) and then document the logic behind that approach within the requirements, your client is far more likely to be collaborative (they usually love feeling involved, don’t they?!). They’re more likely to provide their approval, and further down the road when they’re doing User Acceptance Testing (UAT), they will have a head start on understanding the “why” behind your team’s solution.
Requirements Management Tools
You can manage requirements on something simple like Google Sheets, but there are also specialized platforms designed to help define and track requirements as the project evolves. Here are a few examples, and you can read more about these in this requirements management tools overview:
Understanding The Requirements Gathering Process
While requirements gathering should start as soon as an engagement starts and throughout your entire project life cycle, the bulk of your requirements documentation for something like a full website build should land after discovery (content strategy, site mapping, wireframes, designs) and before development. It’s never too early to start gathering and documentation project requirements. In fact, start yesterday.
It’s never too early to start gathering and documenting project requirements. In fact, start yesterday.
Here are the steps on how to gather requirements, taking you through a complete requirements gathering process. These steps will help you to finalize requirements documentation through team collaboration, checks and balances, and client education.
1. Take Notes
In every meeting you’re in—whether that be internal with your project team or external with your client—always take notes. Never assume someone else is taking them. Chances are…they aren’t.
Digital Projects Managers are not secretaries, but there is an expectation that we capture action items, needs for clarification, opportunities for additional research/discussion, and any other important information discussed in meetings. In the moment, it may be easy to assume everything being discussed will be remembered, but 3 months and 15 meetings later, your team and your client will thank you for having a record of those discussions to look back on.
Read more on great note-taking strategies or check out some of my recommended procedure for taking requirements notes here:
- Before going into your meeting, prepare your notes document to reflect your agenda so organizing the action items and points will be easier. For example, your agenda may have the points, “Paypal integration”, “Checkout landing page”, and “Promotional code functionality”. On your notes document, add those items as headers and include any points you or your team may want to bring up underneath the corresponding header. This way, you’ll remember to bring up what’s needed while capturing related information in an organized manner.
- After any meeting, schedule 15-30 minutes for yourself to review your notes, digest what was discussed, prioritize action items, identify challenges/red flags and needs for clarification or additional meetings.
- Send your notes to your internal project team. Have them review and verify what you’ve identified as action items, red flags, etc.
- Once the team has given you their blessing, send your notes to your client.
- Finally, leverage your notes as reference for creating tasks (e.g. JIRA tasks) out of each action item. Add any new information into your requirements documentation, and schedule any needed meetings for additional discovery or discussion.
- Save your notes in a shared space, perhaps within a “Meeting Notes” folder of a Google Drive instance, so that your project team members are able to easily access and reference them in the future.
2. Go Over The Creative Requirements
Don’t leave design and styling decisions up for grabs: provide creative requirements whenever possible. If your timeline and budget allows, creative guidance is invaluable for developers. While you may find that rare unicorn developer who doubles as a designer, more often than not you’ll find a developer is best at developing; do not task them with the design.
At the very least, provide a style guide—even if the style guide is as bare bones as font and brand colors. Ideally, you will have both wireframes and full user interface designs for mobile and desktop across all page types.
Once you have gathered them, upload all the creative assets to shared space for full team access and visibility. Make sure you’re saving the final versions of these designs in one place, separate from any older versions, so your team is absolutely certain they are referencing the final creative assets.
When creative is finalized and formally approved by the client, it’s valuable to schedule an internal handoff meeting for the project team; this presents an opportunity for your creative team members to smoothly hand off their work to the development team members. It also allows for discussion to ask questions, clear up needs for clarification, and reduce the risk of developer assumptions—an otherwise dangerous game. Your “creative team” may not be limited to your UX/UI designers; this may also include a digital strategist to speak for the user journeys, or a content architect to discuss the sitemap. Include everyone who contributed to deliverables thus far, which will inevitably play into the development, production, and implementation ahead.
3. Make Annotations
Once you’ve handed off the deliverables from creative to development, it’s time to annotate your page elements across all page types. This can include static vs. carousel hero images, dropdowns vs. text fields in webforms, dropdowns vs. slideouts, pop-up modals vs. new page loads, and any other functionality on each page type.
Only annotate pages once they are absolutely final. There is nothing worse than having to re-annotate a page with 35 elements on it just because a pagination bullet shadow was removed (okay—there are worse things, but you get my point).
Typically, I start by annotating the mobile page design and then I annotate the corresponding desktop design—only where functionality of that page differs from the mobile experience to the desktop experience. Why start with mobile? In the digital industry, it’s most beneficial to keep a “Mobile First” mentality in mind when producing a digital solution. That being said, you may very well have a client in the Industrial or Mechanical Product space whose users access their platform via warehouse desktops and are unable to access via mobile devices. In that case, by all means you should accommodate and annotate the desktop page designs first.
My point is this: whether mobile, tablet, desktop, portrait, landscape, what have you … annotate the format or type of page design first that makes most sense. Then, adjust the remaining designs for each page if/as needed. I include the following note within my requirements documentation to disclaim this intent:
Once your creative is annotated, load the images into your documentation. Do this in an order that makes most sense. If a user journey exists, it’s most beneficial to leverage this as guidance for the order in which you organize the annotated designs. For example:
- Product Category Landing Page
- Product Detail Page
- Product Customization Page
- Checkout Page
- Payment Page
- Confirmation Page
If you do not have a user journey to leverage, then organize your annotate page designs in a way that makes sense for your client. Homepage is always a safe bet for a first design to display in your requirements documentation – likely it’s the page design with which your client is most familiar at this point. Remember: at this point of the engagement, nothing you are including within the requirements documentation should be a surprise for your client. This is not a vehicle for presenting anything new to them; this documentation formalizes what has already been discussed, decided, and (at least softly) approved by your client.
4. Write The Requirements Document
The fun part.
As you dive into documentation, remember: your first go at requirements documentation will be the most difficult. Why? Because you do not have a previous document from which to leverage (aka COPY-PASTE). Lucky for you, dear DPM friend, this article includes a requirements documentation template to serve as a foundation for you.
As displayed in this template, I organize my requirements documentation into four parts:
Includes the numbers from your annotated design. If your page design has 8 elements on it, you will have 8 annotations, and your annotation column will have 8 rows
Includes element titles, as they relate to each annotation
- Functional requirement
Includes a definition (the requirements, spelled out) for each element
- Admin/CMS functionality
Define any administrative and/or CMS functionality, as is related to the corresponding element
5. Hold An Internal Review
Once you have completed your first draft of the requirements documentation, crack a beer. Or a root beer. Enjoy it. But only one. There is still work to do. And I promise: the work up front is worth it.
In this part of the requirements gathering process, you schedule another internal meeting with your project team to review your requirements documentation all together. This is a final internal checks and balances to ensure your understanding of the implementation. This is imperative. Because guess what? As the DPM, you manage the client expectations for the implementation. Your understanding of it is critical to the success of the project and your client’s happiness.
If possible, have the team review your requirements documentation prior to the meeting so they’re able to come ready with their questions and/or feedback. Use the meeting to discuss any questions, and feedback on the requirements. Identify gaps in understanding nd verify consistency of the requirements documentation.
As part of the internal review phase, you’ll need to make any necessary revisions to the documentation, based on your internal discussion. Finally, re-send the revised requirements documentation to the team for one final blessing.
Once the internal project team provides their final approval of the requirements documentation, save the document as a PDF (here’s some info on PDFs and how to edit PDFs) to ensure that remains in its finalized state for the next step: task buildout.
6. Build Out Tasks
Provide the PDF version of the requirements documentation to your development team. Ideally, your developers or development lead will perform the task buildout for the build. While some organizations may operate under a process where DPMs build out all tasks, I prefer to have developers build out their own tasks; the handful of hours it takes for them is worth it. This allows developers to build out tasks in a way that suits their development approach.
You can still provide useful guidelines for your team as they build out their development tasks. Here are some example guidelines for a website build:
- No task should exceed 8 hours
- Follow verbiage specific to JIRA, but applicable across other tools
- Each page type element annotated in the requirements documentation should have its own subtask
- Mobile and desktop should have separate stories
- 1 sprint = 1 week
- Use time estimates (story points or hours)
After task buildout, you will be able to get a final hour estimate. For example, if a developer builds out all of their tasks with hour estimates and their hours total 150, then…
- Assume your developer is single-threaded (focused only on your project)
- Each week you will get 35 hours of their time
- 150 hours total at 35 hours per week = 4.3 weeks
- Add QA, which should typically be 20% of your development time
- 150 hours development = 30 hours of QA, or 1 week
- Now, you can confirm your development timeline is 4 or 5 weeks followed by 1 week of QA.
At this point, you compare that projection to the timeline that has been communicated to your client previously, and manage accordingly if/as needed. For more on estimating projects, see this complete project estimation guide.
7. Hold An External Review
At this point, you have:
- Written your requirements documentation
- Confirmed the documentation with your internal project team
- Built out development tasks, based on the requirements documentation
- Confirmed the projected timeline through QA, based on the requirements documentation
It’s time to present the requirements documentation to your client. Provide this as a PDF to ensure no edits are made. Include a message immediately requesting a meeting to walk through this documentation together. This (1) exemplifies investment on your part to ensure client understanding of the digital solution and (2) will be insurance for you, as a DPM, to be able to say “I told you so” (but far more eloquently) when scope creep inevitably rears its ugly head later on in the process.
Educate your client. Walk them through this precious documentation you so painstakingly put together for them. You may have clients who has a rich history of implementing digital solutions. But I’m betting that more often than not, you don’t and they haven’t.
While your client may scoff off a documentation walk through, you may be surprised with their interest and appreciation in having the ability to walk through the documentation with you. Remember: they are the experts of their business. You are the expert of the digital solution you’re offering them. They are paying you for this solution. Educate and empower your client. They (probably) deserve that. Kick off the conversation with making sure they understand this is the time to ask whatever questions they may have, ask for clarify, and that no question is a dumb question. They will appreciate that. Worst case scenario: they decline the request for a walk through. At least you can say you offered. And I will tell you this: I have not had one client decline this request.
Once the client has confirmed their understanding of the requirements documentation (whether or not they decided to do a walk through with you), it’s finally time to receive formal approval. I highly recommend receiving a signature for this requirements documentation prior to starting any development whatsoever. It seems like a given – but this dependency is abused more often than not. Do your very best to adhere to it.
Send the signed and approved requirements documentation to your team and save in a shared space, so there is a formal indication that development may begin.
Educate and empower your client. They (probably) deserve that.
The Wrong Way To Gather Requirements
Below is an example of a not-so-great requirement—an example where requirements management is severely lacking. This is a real requirement that was included within documentation that a real client signed off on for a custom e-commerce website build.
All extensions that exist on the current [VERSION 1 OF UNDISCLOSED ECOMMERCE PLATFORM] website will be implemented and functional on the new [VERSION 2 OF UNDISCLOSED ECOMMERCE PLATFORM] website.
Oh my Lanta. The ambiguity.
While I’m not going to rewrite the multiple pages of technical and functional requirements documentation the sentence above truly deserves, I am going to outline a few questions to break open the requirement and challenge the author to further clarify and document what exactly this means.
- Which extensions exist on the current VERSION 1 of this website?
- For each extension, I want to know:
- Which version is it?
- Who is the creator/source/developer?
- What feature or functionality does it offer?
- Are all extensions capable of running on VERSION 2 of this platform?
- If yes, list out each extension that is capable of running on the new platform
- If no, list out each extension that is not capable of running on the new platform, as well as the replacement solution, whether that be another extension that is capable on the new platform or a custom solution.
- Is there a cost associated with any of these extensions? For each cost:
- Is it a one-time implementation license/cost? Will the cost carry over from the previous license, or is a new license required?
- Are there any subscription costs?
- Will the cost be the same if running on a newer version of the platform?
- Will any additional costs be considered a change order?
While your team may very well know the answers to all of the above, knowing does not suffice. That knowledge must be documented thoroughly. The DPM must manage ask those questions and poke those holes in order to make sure those holes get filled.
The above questions easily prompt a few pages of requirements, depending on the number of extensions applicable to the build. With this particular example, there were more than 100 extensions implemented on the current VERSION 1 of the platform. Needless to say…chaos ensued. I’ll leave the rest of that story to your imagination.
Not sure where to begin?
Becoming a confident, successful project manager is no simple feat—if you’re looking for a good place to start, our online course in Mastering Digital Project Management will light the way. In this 7-week course, you’ll gain access to relevant, practical expertise that will help you lead happy teams and deliver high-value projects in the digital world.
Whether you are formally trained as a project manager or an account manager who has been cast into the role, it’s your job—and privilege—to become a master in the art of managing projects. Our course will equip you with the fundamentals that will help you meet the daily challenges of project management, evolving as a professional in the big, wild world of Digital Project Management.
6 All-Important Requirements Gathering Techniques
It’s imperative that you, as the DPM, remain close to the requirements documentation. After all, these are documents that you can leverage to run budget health checks, give walkthroughs to your client before they provide approval, check off items during the Quality Assurance (QA) phase of the project, use as a guideline for testing features and functionality—and everything in between.
Here are some techniques to help you ensure you’re doing the important requirements gathering work to the best of your abilities:
1. Start Right Away
Requirements documentation shouldn’t wait until all of the discovery discussions have happened, or until after wireframes are made. Requirements documentation should begin as soon as conversations start happening.
It works well to capture all the information and subsequently pare down. Rather than removing information from the document, simply begin to categorize it into (A) what’s included and (B) what’s not included— this way, you’re avoiding that telltale client assumption later down the road (“I could have sworn we talked about this…”). That’s where you pull out your WIP (work in progress) requirements documentation and point out where that information was captured, why it may not be included, the logic behind the decision, and the date this was captured.
2. Make Use Of Templates
Once you have a few requirements documents under your belt, start leveraging them and templatizing them for future use on other projects. Especially if you have a specific focus on e-commerce, or brochureware, or learning applications…you’ll start seeing the functionality patterns surface. Identify where you can repurpose.
I’ve included a few requirements document templates at the bottom of this article.
3. Teamwork Makes The Dream Work
It’s highly unlikely you’ll have just one individual drumming up project requirements—this is where requirements elicitation comes in. If there are different types of resources on a project (e.g. User Experience Designer, User Interface Designer, Software Engineer, Frontend Developer, Digital Strategist, Content Architect, etc.), the requirements for each area of expertise may be authored by the respective experts.
Have you ever played telephone? Of course you have. When a DPM scribes documentation that originated in the mind of a developer (or a strategist, or a designer), you run the risk of something getting lost in translation. In many cases, the conversation about requirements is a winding trail of phone calls, various separate meetings and conversations, etc. This is where is is critical that you, as the DPM, assign out requirements documentation to respective team members in order to elicit and compile requirements.
To help your team with requirements elicitation, make sure you:
- provide documentation templates
- capture and share your notes
- arrange for the right conversations to happen
- facilitate requirements documentation planning meetings and reviews
- put the final touches on the documentation
By the time you start writing the requirements for your requirements documentation, you should already have had multiple points of checks and balances related to requirements, including:
- Client meetings (where designs were reviewed and at least softly approved)
- Shared nots (where decisions were captured, reviewed by both internal and client team, and confirmed as valid)
- Internal review/handoff (where designs were reviewed and page elements were confirmed)
That said, make sure you leverage your team members as you need to complete the requirements sufficiently.
4. Don’t Just Record Requirements—Learn
Do more than take notes. Expect more than resources emailing you a wall of text comprising their portion of the requirements. Take the time to sit down with your team of developers and learn the solutions the team has in mind for implementation. Discuss why and how. Ask questions.
Before you say, “But we only have so much time in the day—and what about the budget?”, understand this: if a solution you’re working on is applicable to more than one project, then this additional time for getting an understanding does not necessarily need to be billable. You’re growing your subject matter expertise that directly improves your day-to-day work.
5. Keep Your Client In The loop
Requirements documentation does not have to be Level 1 Confidentiality with a big red Top Secret stamped diagonally across the front page. While you can absolutely have an internal requirements document where you’re less worried about including more transparent notes, it doesn’t hurt to have a client-facing WIP requirements document.
If you’re not dealing with sensitive information, you can create this shared space through a Google Doc, with permissions enabled for the client to comment.
If you are dealing with sensitive information, share a version of the requirements document on a weekly basis to provide a client a snapshot of what’s been captured. After all, this is a document they’ll eventually have to sign off on.
6. Assume Your Client Knows Nothing
Rather than running the risk of assuming your client knows more than they do (then having that burn you later on when they truly didn’t know the difference between “plug-in solution” and “custom solution”), assume your client knows nothing. Define as much as you can. How? For each annotation, ask yourself “Why?” five times to ensure thoroughness of each requirement.
Here is an example of asking “Why?” 5 times in order to define your requirements:
Annotation for Registration Page:
User Store Location must be a dropdown selection.
Text field input increases the risk of errors in user entry. Dropdown selection limits the number of options from which a user may choose.
If there was a text field input, “MINNEAPOLIS” could be entered in as “MINNEAPOLIS” or “MPLS” or “Mini-apple-us” and data would be messy. This is not good. A drop down selection limits the options to whichever options the admin enters into the backend admin panel. This limited selection is good, for sake of accuracy.
The client wants to use their user data in order to eventually segment content based on user location.
This client has content specific to location/region based on the products they offer.
Asking yourself “Why?” five times for each requirement also challenges you to really consider the logic behind every element and functionality of each page type. You may be surprised with how much you learn (or realize you need to learn).
Some Expert Tips: How To Write A Project Requirements Document
1. Write Requirements For Global Elements Separately
To eliminate redundancy, cover all global elements in a “Global Elements” section of your requirements documentation. This is applicable for global elements such as your main navigation menu items, anything within your global header, and anything within your footer. Once you’ve written requirements for these global elements, do not bother annotating them throughout the other pages; only annotate elements specific to those pages.
2. Copy-Paste Identical Functionality To Ensure Consistency
This is merely a tip to keep in mind for your (and your client’s) sanity. You’ll see this most with common page elements such as hero/banner images, headers, or “back” icons…among a large number of repeated functionality across page types (not to be confused with global elements). This is not new age Google SEO Strategy where you have to worry about repeating words or phrases, and this is not your Grade 9 English Essay where you have to make the same idea sound profound by rewording it six different times. This is requirements documentation.
3. Acknowledge Admin And CMS (Or Lack Thereof)
When we are so focused on functionality of each page element, it is easy to disregard administrative and/or CMS functionality. If you’re implementing a solution which offers administrative and/or CMS functionality, be sure to include this as its own column in your requirements. Example below:
Requirements Document Template
Requirements Document TemplateThe specifics of your requirements definition will depend on your relationship with the client, your team’s experience, and other factors. However, you’ll still need the basic parts of a project requirements document that gives definition to a feature’s functionality, location, design, etc.
Here are some requirements document templates, along with a digital glossary to help you out:
This content is exclusive to DPM Pro Members!
DPM Pro Members get:
- Instant access to expert-crafted templates to save you time.
- Workshops, mentorship, and community support to grow your career.
- Ebooks to guide you through the PM role.
What Do You Think?
The more requirements documentation you have, the less room for error and assumption there is. The work up front will save you the headaches later on. The checks and balances will benefit your team’s mutual understanding of the project and your client’s expectations of the final product.
Like all areas of expertise: the more you do, the easier it will get. The first requirements documentation I wrote for a full website build took me approximately 60 hours. Now it takes me about 15 hours to do requirements for a website of comparable size. And every hour is worth it. Your sanity will (eventually) thank you.