I'm telling you, its not as clean cut as at most schools. I've gotten a bad grade before and not reacted this way. It is not my ego. I'll give an example: on the syllabus all out of class assignments count for 5 percent of the total grade and there were bout 20. As such, all papers being even, I get an NP rather than a P ( the only grades given) because I was late on an out of class assignment. Has nothing to do with my paper. And I want an independent source to make sure it has nothing to do with my paper. Its not like I got a "C", it is more akin to pass/fail. The arbitrariness is astounding. I mentioned the guy who asked his prof why he got a bad grade and was told: "must happen to somebody" by his prof.. He didn't deserve his grade either. This happened to 25 percent of the class.
You are making less and less sense as you continue to post in this thread and it is becoming increasingly apparent why you did poorly. You receiving an NP because you turned in an assignment late isn't arbitraty at all... it's completely expected. You turn in a late assignment, you get penalized.
Regarding the random tale of your classmate - your professor is absolutely right that receiving a low grade "must happen to somebody." You've already mentioned that is the school's policy. Guess what? Your classmate turned in a horrible paper. If getting a low grade "must happen to somebody," it is going to happen to the students that turn in garbage; and it did.