it goes from "wtf just flickered on my screen" to "wow, that loaded really fast!
but it's an async process that could take longer, so then you get into "well if it's <200ms we won't show a spinner, but if it takes longer we will..."
it's a settings page where you're clicking toggles, and each toggle saves automatically when you hit it. so when you click one, you get a short spinner, then a check mark when it succeeds. feels right to me when I'm using it
I wrote a React hook called usePending[1] for this once. It's surprisingly difficult to get right.
[1] https://gist.github.com/cmmartti/4f7833292b9d277685fc0813532...