It's memorization insofar as you can do all of that practice and become proficient at solving math problems without really knowing what they mean or why the steps work. You're regurgitating what you were taught, not making connections and using your understanding.

You used math as an example of a subject where tests are used to check understanding. I disagree, because most people that I know who did well in math did so by being good human computers, not by understanding anything.

I expect that doesn't continue to be true at the grad level, but most people don't get that far.