The peak-end rule: designing what people remember

The peak-end rule, from the work of psychologist Daniel Kahneman, says people judge an experience mostly by two moments — its emotional peak and how it ended — not the average of every step. Design those two points deliberately and a flow is remembered as better than the sum of its parts.

What is the peak-end rule?

Memory is not a recording; it's a highlight reel. When people recall using a product, they don't average every screen — they retrieve the strongest moment and the last one, and let those stand in for the whole. A long, slightly dull flow with one delightful beat and a clean finish beats a uniformly fine one.

Why does the ending matter more than the middle?

The last impression is the one that's still warm when the person decides how they feel. A rough middle can be forgiven; a bad finish colours everything that came before it. This is why abandoned states, error screens, empty states and confirmations deserve as much care as the hero — they're often where the memory is set.

• Find the one moment worth making genuinely delightful — and invest there.
• Design the ending of every flow on purpose: a confirmation, not a dead end.
• Spend extra care on the low points — errors and waits — since dips are remembered too.
• Don't spread delight evenly; a flat, pleasant average is forgettable.

How we use it

We map the emotional shape of a flow before we style a single screen, then decide where the peak should be and how the end should feel. It's the cheapest way to make a product remembered fondly — you're not improving everything, you're improving the two moments that get remembered.