Any Introductory Education textbook will tell you that not everyone learns the same way. Some people are auditory learners - all you have to do is TELL them how something is supposed to be and they've got it. Other people are tactile learners - these are the "learn by DOING" folks. Visual learners need to SEE the message you are trying to convey - these are the people who need to show ever single miniscule step in a math problem in order to get to the right answer. You can explain something until you are blue in the face, but if the person you are teaching is not an auditory learner, you're just wasting your breath.
I say all this to say that it is important for teachers (no matter what you teach) to include teaching methods that will touch base with all types of learners. Otherwise, you are going to end up leaving some very frustrated students behind.
I'm very much a visual learner. That's not to say I can't learn anything at all from someone explaining a technique. I can intellectually understand the concept (as long as you communicate your concept clearly). But until I actually SEE it in action, I don't completely understand. And after that, I become a tactile learner - repetition is my best friend. But if I never SEE it in the first place, there's very little chance that what I'm DOING is actually right.
I feel incredibly incompetent after drills that I never catch on to because I can't see how I'm supposed to get where I'm supposed to be. And it's not the humble "there's always someone better out there" mindset of a good student. It's the "a first kyu should not be this big of a bumbling baffoon" mindset that only compounds the losing momentum issue.
But I will not be defeated. I am going to practice this new thing until I have it down. Even if we never do that drill in class again, I WILL be able to do it. I'm tired of not finishing things.