Key insights
- A spinner tells users "something is happening" but gives zero information about what or how long. That uncertainty is what makes waits feel slow.
- Skeleton screens preview the shape of the incoming content — avatar circle, text bars, image block — so the brain starts parsing the layout before the data arrives.
- The shimmer sweep matters: a static skeleton reads as "broken", an animated one reads as "in progress".
- Match the skeleton to the real content dimensions. A skeleton that jumps to a different layout on load is worse than a spinner.
- For actions the user just performed (posting, liking), skip loading states entirely — render the result optimistically and reconcile in the background.
Do / Don't
- Do: shape skeletons to mirror the final layout, animate them, and keep them under ~2 seconds before showing partial content.
- Don't: use skeletons for sub-300ms loads (flash of skeleton is noise) or mix spinners and skeletons in the same view.
