The Pros and Cons of Big Design Up Front — And What I Use Instead

As a freelance full-stack developer and designer, I‘ve worked on hundreds of projects over the past two decades, from simple brochure sites to complex web and mobile applications. I‘ve experienced firsthand the evolution from waterfall to agile development, and the impact on design processes.

Depending on the client, project, and team, I may use a traditional Big Design Up Front (BDUF) approach, jump right into agile sprints, or more commonly, find a balanced middle ground that I call "Just Enough Design Up Front" (JEDUF).

Practicing the full spectrum of design methodologies has given me a unique perspective on the strengths and weaknesses of each. In this post, I‘ll dive into the pros and cons of BDUF, share my experience with agile and emergent design, and present the JEDUF approach I‘ve found to be most effective for the majority of projects.

What is Big Design Up Front?

Big Design Up Front (BDUF) is a design approach where the majority of the design work happens before development begins. BDUF fits naturally with the traditional waterfall model of software development.

With waterfall, the project progresses linearly through discrete phases like planning, analysis, design, development, testing, and deployment. Each stage is generally completed and approved before moving on to the next, hence the waterfall analogy.

According to the 2020 Stack Overflow Developer Survey, 37% of professional developers still use waterfall for at least some projects, while 87% use agile. While agile has largely overtaken waterfall, BDUF remains a common practice, especially in enterprise IT and government projects.

The rationale for BDUF made a lot of sense when software was extremely expensive to build. It was far more costly to fix fundamental design issues after the code was written than to work them out on paper beforehand. Spending more time perfecting the design was seen as an investment to reduce development effort and rework.

Advantages of BDUF

BDUF still has a place in modern software development. A BDUF approach is well-suited for projects where:

1. The requirements are clear, complete, and unlikely to change much (e.g. a standard CRUD application or straightforward website)
2. Considering the design of the system as a whole leads to better architecture and fewer integration issues down the line
3. Providing thorough design documentation makes the hand-off to development more efficient and less risky
4. The client needs to approve the complete design direction before expensive development work starts

In a BDUF process, designers can focus on perfecting the user flows, visual language, and microinteractions without getting distracted by implementation details. We have the time and space to consider the design holistically, spot inconsistencies, and ensure all the pieces fit together in a cohesive experience.

Disadvantages of BDUF

However, BDUF also has significant drawbacks in today‘s world of customer-centric product design and continuous delivery:

1. It assumes you can fully understand user needs and design the optimal solution up front, which is unrealistic for ill-defined problem domains and innovative products
2. If business requirements or user expectations change during the long development cycle, the design may be outdated by the time it launches
3. You can‘t test and validate design decisions with real users until the very end, so you risk investing heavily in the wrong solution
4. Designers don‘t get the benefit of implementation feedback to refine their designs and strip away unnecessary complexity

According to Wikipedia, a 2018 study by the Project Management Institute found that 31% of waterfall projects failed for these and other reasons, compared to only 11% of agile projects. The flaws of waterfall and BDUF gave rise to agile development as a more flexible, iterative approach.

Agile Development and Emergent Design

Agile methodologies like Scrum and Kanban were created to address the limitations of waterfall. The Agile Manifesto prioritizes:

• Individuals and interactions over processes and tools
• Working software over comprehensive documentation
• Customer collaboration over contract negotiation
• Responding to change over following a plan

Rather than distinct stages, agile projects are divided into short iterations called sprints. Cross-functional teams of designers, developers, and other roles collaborate closely to design, build, and test working features in each 1-4 week sprint.

Design happens continuously alongside development in an agile process. The design emerges incrementally sprint by sprint based on user feedback and team learnings. You only design what‘s needed to support the next chunk of development work.

Emergent design embraces uncertainty and defers decisions until the last responsible moment. Some core assumptions are:

1. You will discover many design challenges and opportunities while building the software that you couldn‘t anticipate up front
2. The tight feedback loop between design and development leads to more relevant, technically feasible solutions
3. It‘s better to get working software in front of real users early to begin collecting data to drive future design iterations
4. Designers and developers should work closely together to rapidly concept, prototype, and validate ideas

Strengths of Agile for Design

While agile can feel chaotic and unstructured compared to a linear BDUF process, it offers compelling advantages for creating user-centric designs:

1. Every design decision is grounded in real user feedback from working software, not educated guesses or stakeholder opinions
2. Technical constraints surface early as developers and designers work in parallel, leading to more pragmatic design choices
3. The steady release cadence provides frequent opportunities to course-correct the user experience based on analytics and usability testing
4. Focusing the design effort on the next increment reduces waste and keeps the design relevant to the evolving product definition
5. Experimentation is encouraged and learning is valued, which fosters design innovation

A 2015 study by the Design Management Institute found that design-driven companies outperformed the S&P 500 by 228% over 10 years. Agile development, with its emphasis on cross-functional collaboration and continuous improvement, has been a major enabler of design-driven product development.

Pitfalls of Agile for Design

However, agile development also presents challenges for creating cohesive, polished, user-centered designs:

1. Decentralized decision-making and lack of a shared design vision can result in a fragmented, inconsistent user experience
2. Slicing the work into narrow vertical increments makes it difficult to step back and see the big picture
3. The relentless pace of sprints can lead to cutting corners and sacrificing design quality for speed
4. Designers have less time for research, ideation, and detailed design iteration with the pressure of keeping up with development
5. Purely emergent design can feel like building the plane while flying it, with a lack of shared understanding of where you‘re headed

A 2017 study in the Journal of Usability Studies analyzed 60 agile projects and found that 77% faced significant UX design challenges, including lack of UX prioritization, insufficient design time, and disjointed experiences between increments. Clearly, agile alone is not a silver bullet for effective software design.

A Balanced Approach: Just Enough Design Up Front

In my experience, the sweet spot for most projects lies somewhere between the extremes of pure BDUF and pure emergent design. I call this balanced approach "Just Enough Design Up Front" or JEDUF.

With JEDUF, you still do some strategic design before diving into sprints, but only enough to create a shared foundation and direction for development. You focus on defining the key user flows, design principles, and technical constraints.

Some key principles of JEDUF include:

1. Designing a strong skeletal experience up front with room to adapt the details based on usage data and team learnings
2. Prioritizing research and design for the riskiest assumptions and most impactful features first
3. Regularly taking a step back from sprints to consider the end-to-end experience and make cross-cutting design improvements
4. Developing a shared language between design and development through lightweight documentation and tight communication loops
5. Staying open to design changes while providing strong rationale grounded in research and first principles

A 2019 McKinsey study found that companies that excel at design grow revenues and shareholder returns at nearly twice the rate of their industry counterparts. I believe JEDUF provides the optimal balance of product design best practices while retaining development agility.

Benefits of JEDUF

In my product design work, I‘ve found a JEDUF approach most suitable for projects with significant uncertainty, complexity, or scale:

1. Creating an early shared vision aligns the team and provides a "north star" for design and development to aim towards
2. Tackling the core experience challenges up front identifies issues while there‘s still time to pivot
3. Timeboxing the design sprints and regularly shipping to production keeps the design relevant and grounded in reality
4. Carving out time to iterate on the design system in between feature sprints maintains coherence and polish
5. Proactive communication between design and development minimizes waste while preserving flexibility

As a concrete example, I recently worked on a project to redesign a complex enterprise web application. We spent the first 3 weeks in an intensive "design sprint" to:

• Interview key stakeholders and sample end users
• Analyze the existing software and map out the core user flows
• Capture the new product vision and priorities in a one-page brief
• Sketch divergent solutions for the main screens and interactions
• Prototype the primary happy paths to get early feedback
• Define the design principles, content model, and technical constraints
• Create a high-level component library in code

At the end of this process, we had a solid foundation to build upon, but with plenty of room to adapt based on user feedback. As we rolled out the new functionality in agile increments, we continually tested our designs and integrated our learnings.

We also reserved 20% of each development sprint for UX improvements and refactoring. This allowed us to keep the user experience aligned as the product grew while still delivering business value in a predictable cadence.

The end result was a modern, intuitive, and scalable application delivered in half the time of a traditional BDUF process. The JEDUF approach provided the right balance of structure and flexibility for the project needs.

The BDUF <> Agile Spectrum

In reality, BDUF and agile represent two ends of a spectrum rather than a binary choice. The right balance depends on the project goals, team skills, and appetite for risk.

Even in a pure agile environment, you need some architectural design before you can build anything meaningful. Emergent design doesn‘t mean zero forethought. At the same time, even the most rigorous BDUF process must adapt to real-world user feedback and implementation constraints.

As a designer, my role is to understand the problem space, explore solutions, and guide the product experience to align with user needs and business goals. No single methodology fits every project.

Instead, I flex my approach based on the situation, from more up-front design when the direction is clear to more emergent design when the path is uncertain. The key is to stay grounded in design fundamentals while embracing agility.

Key Takeaways for Designers and Developers

Whether you‘re a designer, developer, product manager, or other digital professional, here are some key things to keep in mind when approaching software design:

1. Design and development are two sides of the same coin — they must work in harmony to create successful user experiences
2. Big Design Up Front works well when requirements are stable and the cost of change is high, while agile is better for dynamic environments and experimentation
3. Most projects benefit from a middle ground of Just Enough Design Up Front — enough strategic design to create a shared foundation while staying open to emerging user needs
4. Regularly zooming out to consider the holistic experience and design system can provide both flexibility and coherence
5. Foster tight feedback loops between design and development through cross-functional collaboration, open communication, and lightweight documentation
6. Focus the design effort on the highest priority user problems and the most impactful improvements for the next increment
7. Think like a scientist and treat every design as a hypothesis to validate with real usage data
8. Embrace uncertainty and get comfortable making decisions with incomplete information — the magic often happens outside your comfort zone

The art of digital product design is rapidly evolving, and designers and developers must evolve with it to stay relevant. By understanding the pros and cons of different methodologies and adapting our approach to the context, we can create more useful, usable, and delightful software for people everywhere.