Laws / Pointing and time
Doherty threshold
People stay engaged when the system answers in under 400 milliseconds; beyond that, attention drifts.
Trail running guide
12 min read
Press Save and watch how long it takes to answer.
Why it matters
A slow or silent response feels broken even when it works. Instant feedback keeps people in flow and confident the tap registered.
Rules to follow
- Acknowledge every action within 100 ms: pressed state, spinner, or the optimistic result.
- Update the UI optimistically for actions that almost always succeed (likes, toggles, reordering), and roll back on error.
- Show skeletons in the shape of the content for loads over 400 ms, and progress for anything over a few seconds.
- Disable a submit button while its request runs, and label the busy state ("Saving…").