The UX Design Process

The $1 billion button

In 2009, Jared Spool told a story that changed how companies think about design. A major e-commerce site had a simple checkout flow: enter your email and password, then buy. The problem? Millions of people could not remember their password. They would click "Forgot Password," wait for an email that sometimes never came, and abandon their cart. Others refused to create an account at all.

A UX designer proposed a radical change: replace the "Register" button with a "Continue" button and let people check out as guests. No forced account creation. No password wall between the customer and their purchase.

The result? Revenue increased by $300 million in the first year. The company eventually attributed over $1 billion in additional revenue to that single design change.

One button. One insight about human behavior. One billion dollars.

This is what UX design does — and this module shows you how the process works from start to finish.

What UX design actually is

UX stands for User Experience. It is the practice of designing products, services, and systems so that they are useful, usable, and enjoyable for the people who use them.

UX design is not:

• Making things look pretty (that is part of UI design)
• Only about websites and apps (it applies to ATMs, hospital check-in kiosks, even airport signage)
• Something one person does alone in a room with Figma

UX design is a process — a repeatable way of understanding problems, exploring solutions, testing ideas, and shipping products that actually work for real humans.

The Double Diamond — how real design works

The most widely used framework for the UX process is the Double Diamond, created by the British Design Council in 2005 after studying how designers at companies like IKEA, Sony, and Starbucks actually work.

It has four phases arranged in two diamonds:

Diamond 1 — The Problem Space

• Discover (diverge): Go wide. Talk to users. Observe behavior. Gather data. Understand the landscape. You are trying to understand the real problem, not the one your stakeholders assumed.
• Define (converge): Synthesize your research. Frame the problem clearly. Write a problem statement. Decide what you are solving — and what you are not.

Diamond 2 — The Solution Space

• Design (diverge): Generate many possible solutions. Sketch, wireframe, prototype. Do not commit to one idea too early. Quantity beats quality at this stage.
• Deliver (converge): Test your best ideas with real users. Refine. Build. Ship. Measure. Iterate based on real data.

There Are No Dumb Questions

"Does every project really go through all four phases?"

In theory, yes. In practice, the phases overlap and loop. A startup building an MVP might compress Discover and Define into a single week of customer interviews. An enterprise redesign might spend three months in Discovery alone. The key is that you never skip understanding the problem (Diamond 1) even when you are under pressure to jump to solutions (Diamond 2).

"Is the Double Diamond the same as Design Thinking?"

They are close cousins. Design Thinking (popularized by IDEO and Stanford's d.school) uses five stages: Empathize, Define, Ideate, Prototype, Test. The Double Diamond uses four: Discover, Define, Design, Deliver. Both follow the same diverge-converge-diverge-converge pattern. The Double Diamond tends to be used more in professional design teams; Design Thinking is more common in business and education contexts.

Design Thinking in five stages

Design Thinking is the most famous formalization of the UX process, taught at Stanford, used at Google, Apple, and Airbnb, and applicable far beyond software:

How real teams work — Airbnb's design process

Airbnb is one of the most design-driven companies in the world. Their co-founder, Brian Chesky, once said: "We hired our first designer before our first engineer."

Here is how Airbnb's UX team works on a typical feature:

Week 1-2 — Discovery. Researchers analyze support tickets, conduct user interviews, and review behavioral data. When Airbnb redesigned their search experience, they discovered that guests were not filtering by price — they were filtering by vibe. People wanted a "cozy cabin" or a "beachfront villa," not a "$150-$200/night listing." This insight was invisible in the analytics.

Week 3 — Problem Framing. The team writes a design brief: what is the user problem, what does success look like, what constraints exist. They use "How Might We" statements to frame the challenge.

Week 4-5 — Exploration. Designers sketch dozens of concepts. They run "design sprints" (a structured 5-day process popularized by Google Ventures) to rapidly move from idea to tested prototype.

Week 6-7 — Prototyping and Testing. High-fidelity prototypes are tested with real Airbnb users. The team watches recordings, identifies patterns, and iterates.

Week 8+ — Build and Measure. Engineering builds the feature. The team runs A/B tests to measure real-world impact. Data feeds back into the next discovery cycle.

There Are No Dumb Questions

"I am a solo designer. Can I really do all this?"

You scale the process to your resources. A solo designer might compress the entire Double Diamond into two weeks: 3 days of user interviews (Discover), 1 day to synthesize findings (Define), 3 days of sketching and wireframing (Design), and 3 days of prototype testing (Deliver). The phases stay the same; the depth changes.

"What if my team wants to skip research and just build?"

This is the most common challenge in UX. The answer is to make the cost of skipping research visible. The $1 billion button story works because it shows that one research insight generated more revenue than a year of feature development. Frame research as risk reduction: "We can spend 2 weeks understanding the problem, or 6 months building the wrong solution."

The UX designer's toolkit

UX designers use different tools at different stages. Here is what the modern UX toolkit looks like:

Key takeaways

• The $1 billion button proved that understanding user behavior can generate more value than any feature — UX design is a business strategy, not just a craft
• The Double Diamond provides the structure: Discover, Define, Design, Deliver — diverge to explore, converge to focus, twice
• Design Thinking offers five stages (Empathize, Define, Ideate, Prototype, Test) that loop and overlap rather than running sequentially
• Real teams like Airbnb compress and adapt the process to their context, but they never skip discovery research
• The UX toolkit spans research, synthesis, design, and testing — Figma is the current industry standard for the design phase
• You do not need to be artistic — UX design requires empathy, structured thinking, and a willingness to test your assumptions with real people