"There's an old story about a young man who cornered a world-famous violinist and begged to be allowed to play for him. If the master offered him encouragement, he would devote his life to music. But if his talent was not equal to his calling, he wanted to know ahead of time so he could avoid wasting his life. He played, and the great violinist shook his head. "You lack the fire," he said.
Decades later the two met again, and the would-be violinist, now a prosperous businessman, recalled their previous meeting. "You cahnged my entire life," he explained. "It was a bitter disappointment, giving up music, but I forced myself to accept your judgement. Thus, instead of becoming a fourth-rate musician, I've had a good life in the world of commerce. But tell me, how could you tell so readily that I lacked the fire?"
"Oh, I hardly listened when you played," the old master said. "That's what I tell everyone who plays for me -- that they lack the fire."
"But that's unforgivable!" the businessman cried. "How could you do that? You altered the entire course of my life. Perhaps I could have been another Kreisler, another Heifetz--"
The old man shook his head again. "You don't understand," he said. "If you had had the fire, you would have paid no attention to me." --Lawrence Block