Overlearning is a conscious choice.
When you have given yourself a timebox and finished successfully before the end of it, you can spend the remaining term learning even more.
The flip side is this choice: To over-fail.
When you notice in the timebox that you are failing, you could choose to lean into that hard. Choose to fail and fail in many creative ways.
That will be a different kind of learning.
And the next timebox will be richer for it.