Design AtlasEstablished by psychologist Daniel Kahneman and colleagues in 1990s colonoscopy and cold-water experiments. Total duration barely affects how an experience is remembered — only the peak (best or worst moment) and the ending do.
That's why, when designing onboarding, checkout, or refund flows, a mediocre middle matters far less than **investing in the final screen** (a completion celebration, a genuine thank-you). It's the same reason theme parks close the day with fireworks.
The line below traces a bumpy experience; only the peak and the end get a star. The dashed average line stays low, yet the remembered rating still comes out high.
When to use
Prioritise design budget on the final screen of any long flow (onboarding, checkout, a survey). It moves the remembered impression far more than smoothing minor friction in the middle.