Like Paul Patterson at Taylor every drill, every shooting sequence was a competition. Free throws, shooting drills, everything timed and competition was against themselves, a number or the other team (white vs green). The whole idea was that everything has winners and losers and the losers paid a price. Motivation without yelling and screaming. Teaching without bullying and intimidation. Results oriented lessons.
We did similar things at my high school. Was a great teaching tool for concentrating on what you had to do at the foul line. I fully believe we became a better FT shooting team every year because of it.
My youngest son's team does it as well. For free throws his coach usually breaks them into four teams (they practice with the B team) and has team winners and then individual finals where the top 4 compete for a small prize (squeeze bottle, team T-shirt, etc.). It's typically done right after suicides so they are winded. The boys are really into it and it does a good job of recreating the pressure of game situations. They do similar things on other drills as well but the highlight is always the free throw competition.