When Eric was 10, he decided he wanted to play football. He was so good the coach made him quarterback. After one game, he decided he didn't want to be quarterback because, in his words, "Everyone's trying to get the quarterback!" The coach was adamant about Eric's assigned position, so Eric resigned -- with his parents' blessings.
Later he tried soccer. After three games, he decided he didn't like his coach, who yelled at his players for not "hustling." His father agreed that the coach was acting inappropriately, so again Eric quit. Nevertheless, Eric did not become a quitter. Nor did he become a joiner. Perhaps he learned his lesson: organized after-school sports weren't his cup of tea. Through high school and college, he did his own thing -- no sports, no clubs, no fraternities, no political movements, no causes. Despite his lack of organized interests, Eric graduated from college and is now a commercial pilot. He is married and has a child. A quitter he is not.
Children should be free to approach such things as soccer and music lessons with a spirit of playfulness. No child should be required to have a better reason for quitting than, "I want to." A child who is not free to quit becomes increasingly reluctant to join for fear of becoming locked into an activity that seemed attractive at first, but turned out to be something completely different.
This being the rule, here are some exceptions: