Erik asked, "What makes a good teacher?"
I think it's difficult to give a blanket answer that will please everyone, so I'll give a few qualities of teachers whom I admire.
I think the foremost in my mind is their willingness to make mistakes and accept them for such. I've trained with people who try to cover up mistakes and did not acknowledge them as such. I would rather have teachers who are open to being imperfect.
Another quality which I like is for a teacher to let their students be themselves. I don't want to be forced to become a clone of any of my teachers or of anyone else.
The people whom I consider to be my teachers have gotten to know me well enough to be able to push me both physically and mentally without "breaking" me.
Honesty counts, too. Encouragement is, of course, welcome, but I would rather not have everything sugar-coated.