A high school student studies hard for an upcoming test. She prepares herself as well as she can and does the best she can do on the test.
The test ends. The course is over. She moves on to college and a career.
So what didn’t she get out of doing her homework? The grade is long forgotten, and it doesn’t affect her career at all.
She got the experience of setting a goal, preparing to achieve the goal, working hard, giving it all she had, and learning how to do it better the next time. She developed a habit, and that habit is what can stay with her for the rest of her life.
The same is true with music, theater, sports, after-school jobs, and any other meaningful activity at any age. When we give a situation our best effort at any age, we walk away with an enhanced habit. That habit is worth a tremendous amount of value.