Repetition is trusty way to learn something and get skills. I love repetition and truly trust it. It is useful for two kinds of learning --- sudden type like mathematics and gradual type like skills.
In difficult subjects of math, I have to pass a long time with inunderstanding. One day I get to understand them suddenly. Repetition gives me understanding finally, but the effect on the way is invisible. Anyway, that's sure and trusty. I enjoy inunderstanding something. That's a phase of the way to understanding.
Getting skills is visible and different from sudden type. Repeat practices and become good at skills gradually by repetition. Because the result of an intermediate step is visible, it's fun to keep repetition.
However, human beings have wit to escape from tough repetition. To escape from the repetition, human beings often change the way, the purpose and the motivation. A such wit is a kind of skills. But, wit ruins a chance to get knowledge and skills. Must keep a balance.