Animation is a language. Used well, it tells people where things came from, where they are going, and how parts of the interface relate. Used poorly, it is just movement for movement's sake.
The best motion is functional. A modal that appears from the button that opened it creates a spatial story. A list item that slides out confirms a deletion. The person never has to think; they just understand.
Keep durations short, respect reduced-motion preferences, and ease with intent. When in doubt, animate less.



