What kind of experience is it for university teachers to deliberately fail the course?

There was a college classmate named X Xingguo. When he went to physical education class, the teacher called his name and pronounced it X Xingguo. He told the teacher that my name was Guoxing, not Xingguo, but in the second quarter of physical education class, the teacher still pronounced it X Xingguo. He had to tell the teacher again, teacher, you read it wrong, but I didn't know that the teacher suddenly gave him a white look and said, "I know your name is X Guoxing." Then the PE teacher hung him up at the end of the term. His physical education class is the highest level in that basketball class. I feel sorry for this classmate who could have kept his graduate degree, because this physical education class was ruined. I think this kind of teacher is really irritating.