It's been my experience throughout school and even to an extent college that I fared better on my own, that teachers would try to impose some of their own dumb ideas of how to learn onto me, and whenever I made the mistake of trusting them, it would not just not be helpful, but actually make my learning worse. At some point that let to me completely giving up on teachers and trying to teach myself everything, which surprisingly enough, has seemed to work quite well with most things I've encountered up till now.
... if a teacher regards me as a blank slate and tries to teach me according to some "traditional" guidelines in a rather lockstep fashion, then that isn't just boring, but my mind actively rebels against it. It also grinds my gears when teachers rehearse common platitudes and rules in the name of 'musicality', which I've already read and heard a dozen times before. My natural default is to think deeply about something e.g. a technical problem, and come up with half a dozen possible solutions.
Common advice such as 'do scales/Hanon exercises' don't cut it, because I immediately get dozens of questions and alternate methods swimming in my head.
Is it to develop some kind of flexibility?
Wouldn't that be better done hands separate, focusing on each note?
Wouldn't that be better done fast rather than slow? Or slow rather than fast?
If the whole point is to practice certain hand motions, why wouldn't you just focus on the hand motions themselves?
Or is it hand coordination? Isn't the whole point to figure out how the technique works -- in that case, what's the point of assigning an exercise and having the pupil struggle with it, doing it wrongly? Why wouldn't you just demonstrate it?
Or is it so that they figure out the technique themselves? Then, why wouldn't you encourage them to experiment on their own accord subject to a set of principles?
Or you could focus on technical sections of pieces and use them as exercises.
Or, if you wanted to really go all out on hand coordination, you could give the student a Bach fugue and ask them to struggle with it.
Progress needs to be gradual and you shouldn't get ahead of yourself? But what if they do and it works out for them, how would you know if you don't try?
Or if you know that the piece is damn easy for them, but want them to work on a very specific voicing task or something, you need to state that directly.
The fact that piano teachers have often suggested that I do things as they suggest rather than the methods I figured out, only to find that my methods worked for me and that what they suggested often simultaneously made practice a chore as well as relatively ineffective (and I would hate to learn to hate the only thing I'm passionately interested in), makes me wary of trusting a teacher blindly.
At the same time, teachers often don't understand what I'm trying to convey when I explain my idiosyncratic understanding of how I think something works musically or some way in which I tackle something, and eventually just tell me to do it because it works and is the right way to learn, which then forces me to trust them blindly.
Is there a way to find out if a teacher is good before taking a lesson with them? What kind of questions should you ask a prospective teacher beforehand?
There is only so much you can gain from the first few lessons with a teacher, usually it takes at least a term of work with them to come to some kind of real conclusion whether the lessons are good or not.
There is only so much you can gain from the first few lessons with a teacher, usually it takes at least a term of work with them to come to some kind of real conclusion whether the lessons are good or not. Unless you are lucky and find a teacher where your relationship just clicks it does take time for both you and the teacher to get to know how each other works.
It is also tricky to figure out whether the improvement is actually due to the teacher or not. I have felt significant improvement in my playing every few months or so when I've been learning on my own, so there is always that opportunity cost.
There is a moment where you need to trust a teacher to take you in a direction you have never considered, even if that means going against techniques or theories you have developed yourself. You need to give yourself permission to become vulnerable. You don't have to stick with the idea if it does not work, but you should seriously consider trying it before dismissing it. One of my teachers used to say "you don't have to do anything I tell you, but you need to do something," meaning, the commentary wasn't a directive to follow, but an encouragement to think of a solution, the commentary being a starting point.
Why not continue learning on your own until you have saturated that aspect of your learning? If you find you have "significant" improvement every few months on your own there is no point in getting a teacher until you hit a dead end. If you constantly have that doubt whether it is the teachers efforts or your own which are improving you, you may not be ready for a teacher, ultimately it is more your own effort (since lessons time vs personal practice time should have a large difference) with the focus of your attention helped by the teacher. My higher advanced students don't use me so much to tell them how to practice etc but help them find direction and advise them where they should be focusing their attention and that in itself is valuable teaching for the more advanced. There are so many options and pathways it is often good to have an advisor who can go through the wilderness with you.It is also not easy to admit ones weakness and where one simply "does not know they don't know" or "knows they don't know" but ignore it. So self learning can help you reveal your weakness if you are honest enough and then studying with a teacher can aim to address those holes.