Here’s a Washington Post article about an experiment. The newspaper asked world-famous violinist Joshua Bell to dress down and perform as a street musician at a DC metro stop. Hardly anyone paid attention. He earned $32.17 in tips. People routinely pay over $100 for a chance to listen to Joshua Bell in a concert hall, but he earned an average of about $0.03 per passer-by that day.
Suppose Bell were trying to support himself as a street musician. What might he say to himself after a disappointing day at the metro? That if only he had practiced a little harder he would have made more tips?