My teacher, on his piano, had a tiny wicker basket, the bottom of which contained a cutout piece of paper that said, “Deposit Brain Here”. And while this anecdote will ring true in the ears of any teacher who has taught a know-it-all, it must be balanced against the reality that we are instructing people who are coming to us to better understand singing, breathing, and basic vocalism; not because they have never heard of it.
Even so, a student should simultaneously assume going in that they know some things and that they know very little. And this last part is essential. One should allow themselves to have preconceived notions upset. It is even entirely possible that what a teacher tells you might run quite contrary to your existing notion of singing (or whatever subject). But when you say “why?” or "how?", a teacher should have an answer, and it should make sense. I am a pretty big believer in the Socratic idea of people having some existing knowledge inherent in us that study helps to confirm or awake; the idea that much of learning is a sort of “remembering” is not far off the mark as far as my experience has shown. In the end, neither the know-it-all, nor those of blind faith stand to gain much.
To this end if somebody tells you something and it makes sense, you should trust them. If someone tells you a series of things that make sense and turn out to be true, you should trust them. If somebody tells you something that is contrary to what you might have initially thought, the trust you give them should be based on their explanation having 1) a sense of its own, as well as 2) your having found them to have been correct in the past. And here is where we come to what what is required of the student-
As much as it is the right of a student, for all their invested time and money, to expect that a teacher be effective in their instruction and guidance, the teacher has a right to expect certain things of the student:
Every student owes the teacher the benefit of the doubt that some things take time to become apparent, and that the truth of some things are only finally learned through experiencing that which has been explained. This necessary patience is often mistaken for unconditional trust.
No student has a right to expect results or that the truth of instruction will make itself apparent without practice. Specifically, if a teacher has suggested a manner or way to practice, and this is not followed, a student has no grounds to judge effectiveness.
All people, teacher and pupil alike, are operating from within the framework of their education and experience and cannot possibly know everything. Though no one likes to admit weakness, a good teacher will happily make clear what they do know and what they don’t. And the student should expect from their teacher that they be able to say, “You know, I don’t know that, but I can find out.” or “I don’t know that, but I know someone who might”. I have seen far too many teachers, fearful of appearing lacking, or scared to lose their grip of awe over the student, faking their way through gaps in their knowledge. And this is the balance. Students should be alert for this. This is protecting their investment. Students, be honest about your efforts and attempts, just as you expect your teacher to be honest about their instruction. And teachers, we must be honest. We can only share what we have, not that which we do not.