So a 17 or 18 year old kid needs to be held to the moral standing of an adult male football coach?
Most of the time kids are punished because of unattainable expectations. That has nothing to do with effort. 4 and 5 star players all have high expectations and yet most don't live up to it. Should a kid be punished because a head coach misevaluated his talent? That's what happens most of the time, and that's why this practice is shady and unethical. If effort was the reason then Alabama seems to have a huge problem with players not giving effort, but I don't think that's the case.