Picture a student who started piano at age six. She is now eighteen. She has performed in front of strangers more times than she can count. She has passed the highest levels of national examination. She has played for people with dementia who lit up in ways their families hadn't seen in years. She has published original music. She has taught younger students. She is about to leave for college — and she still practices piano, not because anyone is making her, but because she has become someone...