215
perceived performance
How fast it feels. A slow task that shows progress feels faster than a fast task that freezes.
What is perceived performance?
Perceived performance is the user’s sense of speed: immediate feedback, stable layout, progress for long work, optimistic updates where rollback is safe. It is not lying about a finished save. Indeterminate spinners on long jobs feel slower than a real progress state.
Why does perceived performance matter when vibe coding?
Models await the server before painting any response to a click. The button looks dead. Name immediate feedback.
How do you do perceived performance?
Acknowledge the click in the same frame. Skeleton or optimistic UI where honest. Long jobs get a state and a completion, not a frozen tab. Do not fake completion.
How do you ask a model for perceived performance?
Improve perceived performance of (action). Acknowledge the click immediately. Show progress if it can exceed a beat. Do not block the whole UI on the network. Do not show success before the server confirms a destructive or paid action.
What goes wrong with perceived performance?
An optimistic success on a payment. Perception does not outrank truth when money moved or did not.