W. Somerset Maugham said this quote

“ Monsieur Foinet got up and made as if to go, but he changed his mind, and, stopping, put his hand on Philip's shoulder.But if you were going to ask me my advice, I should say: take your courage in both hands and try your luck at something else. It sounds very hard, but let me tell you this: I would give all I have in the world if someone had given me that advice when I was your age and I had taken it.Philip looked up at him with surprise. The master forced his lips into a smile, but his eyes remained grave and sad.It is cruel to discover one's mediocrity only when it's too late. It does not improve the temper.He gave a little laugh as he said the last words and quickly walked out of the room. ”