"The first rehearsal of the symphony was terrible, but the hornist did, in fact, come in on cue. I was standing next to Beethoven and, believing that he had made a wrong entrance, I said, "That damned hornist! Can't he count? It sounds frightfully wrong." I believe I was in danger of getting my ears boxed. Beethoven did not forgive me for a long time."
January 1, 1970
https://en.wikiquote.org/wiki/Symphony_No._3_(Beethoven)