I had an old school Japanese professor in engineering who gave a test that had a 0% pass rate. He then begrudgingly gave us 3 days to retake the test. The instructions weren't clear, so I redid all of the questions that I got wrong. When I got the test back with those questions wrong, I went to his office hours to ask why. He then proceeded to scream at me " You do all! You are lazy!". That one stuck with me for a long time.