Frédéric Chopin said this quote
“ Kalkbrenner has made me an offer; that I should study with him for three years, and he will make something really - really out of me. I answered that I know how much I lack; but that I cannot exploit him, and three years is too much. But he has convinced me that I can play admirably when I am in the mood, and badly when I am not; a thing which never happens to him. After close examination he told me that I have no school; that I am on an excellent road, but can slip off the track. That after his death, or when he finally stops playing, there will be no representative of the great piano-forte school. That even if I wish it, I cannot build up a new school without knowing the old one; in a word : that I am not a perfected machine, and that this hampers the flow of my thoughts. That I have a mark in composition; that it would be a pity not to become what I have the promise of being... ”