well, maybe the guy was shooting only 3-pointers in drills and scrimmages at practice, and someone who shoots a 3 pointer (especially near the top) should always immediately run back to defense. If this shooter missed the three, and ran back, he would find himself defending a fast break, which usually results in an inside shot attempt (layup/dunk), so he would get some practice defending inside shots.
thats the only way i can think of it.