when I explain that he needs to apologize because he let them (and us) down, disappointed them, he says that their disappointment is their own fault because their expectations are never going to come true.
The expectation is that he does his own work.
period.
You can't let him argue this with you. It's the line in the sand. It has nothing to do with perfectionism, or failure. Don't let him muddy the waters.
The apology is because he broke the trust that exists between students, and also between students and the teacher.
You break something, you apologize.
