After developing his special relativity theory, Einstein needed to take a break from developing his general relativity theory – to go study tensor mathematics!
We talked about this in a YouTube #short.
We have a bit more depth here, in this full-length YouTube.
Similarly, after Luke Skywalker had learned to use the Force, and had vanquished the Death Star, he needed to study with Jedi Grandmaster Yoda to deeply master his use of the Force.
In the associated YouTube vid, we share a bit from the book, Einstein in Bohemia, which you can find HERE.