Knowledge which is acquired under compulsion obtains no hold on the mind.

Anything learned purely to satisfy somebody else leaves as soon as the pressure does, which is why so little of school survives school. Retention runs on wanting to know, and wanting cannot be installed by force, in yourself or in anyone else. Compulsion does produce compliance, and compliance looks exactly like learning until the day the knowledge is needed.

If you are trying to learn something and cannot make it stick, find the question inside it that you actually care about. If you are teaching, spend your effort on making somebody curious rather than on making them study. An hour of real interest holds better than ten of obligation.