Teams often fall into two categories: those eager to see a design or prototype quickly, and those who insist on having a comprehensive Product Requirement Document (PRD) before proceeding.
Of course, it’s not always so clean-cut. In high-ambiguity situations, the design process itself can help create the definition needed to even begin writing a useful PRD. A rough PRD draft may come first, even if key parts are still fuzzy.
That’s why it’s more helpful to view prototypes and PRDs as complementary tools, not competing ones. This shows the tension between wanting to move fast and needing a clear understanding of what we’re building and why. However, viewing it as an either/or scenario misses the essence. Prototypes and PRDs fulfill distinct roles, and their true value emerges when they are used together, deliberately. When treated as complementary tools, not locked into a fixed order, they help teams think through ideas more clearly and make faster progress
Why a single artifact can’t convey the entire narrative
Prototypes are excellent for transforming ideas into something tangible. They illustrate a real experience, and help teams have good discussions. However, they don’t fully explain why a feature is needed, the constraints that influenced its design, or how its success will be assessed.
This is where PRDs prove essential. A well-crafted PRD outlines the reasoning behind the project, detailing goals, tradeoffs, technical aspects, and business context. Yet, even the most comprehensive document can’t replicate the actual product experience.
Finding the right amount of detail can be challenging.
PRDs that are too detailed can be hard to interpret, whereas those that are too vague can be non-starters and lead to confusion. Prototypes serve to ease this tension by showing not telling.
Individually, each tool has limitations, but combined, they create a fuller picture of the what, why and how. The prototype shows the idea, the PRD explains it. You need both to tell the full story.
The case for working in sync, not in silos
When teams develop prototypes and PRDs simultaneously, the give-and-take sharpens both the vision and the details, each offering a different lens for understanding the work. Together, they form a mutual reference point, something everyone can comprehend, engage with, and rely on.
This method also reduces “work-about-work.” The meetings, back-and-forth clarifications, and redundant tasks that accumulate when teams lack a common frame of reference. Using both tools allows everyone to work more efficiently and spend less time translating ideas or resolving misunderstandings.
When design and documentation evolve together, teams are better informed and aligned. Instead of scrambling to catch up or fix confusion after the fact, teams can stay in sync and work things out as they go.
The true meaning of “living” and its importance
For a prototype or PRD to be effective, it must mirror the team’s current mindset. The advantage of considering these tools as living artifacts is that they evolve in tandem as the project progresses. However, “living” requires active maintenance. This involves revisiting the PRD after a significant design alteration or updating the prototype when priorities change. Without ongoing attention, these tools lose their utility. To remain beneficial, living artifacts need someone to maintain them, which involves clear ownership, shared access, and regular reviews to ensure they continue to accurately represent the current situation.
Common challenges and how to prevent them
It’s common for prototypes and PRDs to fall out of sync—and when they do, things can get messy. People start working from different assumptions, decisions get made on outdated thinking, and the team can lose sight of the problem they’re actually trying to solve. When a prototype dominates too early, it can bias the team toward a single solution before fully exploring the problem space, narrowing creative thinking and leading to rushed decisions.
These challenges can be avoided with a few intentional practices:
- Clear responsibility: Assign someone to ensure every document remains accurate and current.
- Shared accessibility: Ensure the entire team can easily view and reference both the prototype and PRD.
- Intelligent cross-referencing: Create links between the two. The prototype should refer back to the appropriate requirements, and the PRD should highlight important moments in the prototype.
Keeping prototypes and PRDs in sync doesn’t require perfection, just a bit of discipline and a shared understanding that both tools only work when they’re kept aligned.
A more human approach to product development
Teams thrive on clear expectations and mutual understanding, not just on procedures or tools. When everyone understands what they’re building, why it matters, and the kind of experience they’re aiming for, collaboration feels easier and the outcomes are better.
Prototypes show how things might work. PRDs explain why they matter. Used together, they bring clarity to both the experience and the reasoning behind it. Prototypes encourage participation from a variety of voices, transforming the process into a collaborative effort rather than a directive one. This collective sense of ownership typically results in more robust ideas and more committed teams.
This approach goes beyond just efficiency; it’s about respecting the natural ways people think, communicate, and collaboratively solve problems.
Implementing a practical process
A good process requires shared practices, cultural reinforcement, and a bit of structure. Here are some simple ideas:
Begin every project with a shared document
- Don’t wait for a finalized PRD or a polished prototype. Start with a shared working document early on that links to both artifacts. This promotes transparency and keeps everything connected from the beginning.
Embrace unfinished work
- Encourage sharing early—rough drafts, initial notes, and half-formed ideas. When teams view work in progress as an opportunity rather than a risk, better discussions occur sooner.
Focus reviews on outcomes, not just artifacts
- Steer clear of questions like “Is the prototype complete?” Instead, ask “Do we all understand what we're creating and why?” Use the prototype and PRD together to address that.
Keep alignment simple, but consistent
- Formal check-ins aren’t necessary. A brief async comment thread, a shared Slack reminder, or a weekly review loop can keep things aligned without hindering progress.
Set an example
- When team members keep both artifacts updated and link them with intention, it sets the standard for everyone else. Clarity spreads when it’s evident in the work.
Prototypes and PRDs work together. They form a cohesive partnership that enhances each other’s strengths.
To see them as standalone entities or as replacements for one another is to overlook their genuine significance.
The true depth of understanding emerges when you combine these elements, melding visuals with requirements, and merging tangible experiences with detailed explanations. When teams intentionally employ both tools in concert, they not only hasten their advancement but also amplify their collective capabilities.
This synergy creates a dynamic where creativity and clarity flourish in unison, leading to more innovative and effective outcomes.
