I think this is a very incompetent performance, because make-up lessons are only used to explain after class to some students who have poor academic performance and can't keep up with the progress of the class. However, if all the knowledge that should be taught to students in class is put into making up lessons, it is a means to earn illegitimate interests by using one's own duties. If some students don't attend make-up classes, it shows that they lack knowledge in this field and lag behind others, which is a very bad phenomenon.