Naven
Glossary
Animation
Motion used to explain a change rather than to decorate one.
The useful kind answers a question the reader would otherwise have to work out: where did this panel come from, what just changed, is something still loading. The useless kind delays the interface to show off.
Duration is the tell. Interface motion works between roughly 100 and 300 milliseconds; longer than that and the reader is waiting for the software rather than the other way round.
Where Naven stands
Naven's motion is transform and opacity only, interruptible, and absent where it would add nothing.