This takes a turn, so read the whole thread.
The piano professor I started with in my undergrad program was rather famous and well respected, but he was verbally abusive to me. Within a few weeks I had enough and demanded reassignment. I later found out that he was that way to everyone. The teacher I had for the rest of my undergrad was absolutely phenomenal, and continues to be an inspiration to me as a musician who is soft spoken and humble despite their enormous ability.
1/2
Today I met a fellow classical pianist who attended the same university (I believe several years after me) and had the same professor I started with, but he was both *physically* and verbally abusive to her. Apparently he used to hit her when she wasn't playing up to his standard. I was shocked, but not surprised. This person did not feel comfortable going to the head of the department as I did, however. She stayed with this professor all four years.
2/3
@voltronic agree.. their way of teaching really ruined future life of so many good musicians...