In first year university, I did a semester of Latin. For the first few weeks I was feeling very motivated; then depression hit me. I stopped going to class. What I should have done, is go see a doctor or psychologist, and got a letter saying I was depressed, and given it to the university administration, and I'm sure they would have given me some form of special consideration. But I didn't do that (it simply never occurred to me that I could do that, I wish it had.)
Anyway, since I'd missed more than half the semester of lectures and tutorials, I was thinking to myself - why bother turning up to the exam? I know I am going to fail anyway. But, I said to myself, I should go, you never know, I might somehow scrape through.
So, I sat down at the exam. I think I got the first page right. The subsequent pages, I had no idea. I sat there and waited until they let me leave early. (The university had some rule, you couldn't leave the exam early until after the first half-hour was up, or something like that.)
I waited for my results, I expected to fail. I was very surprised to find out I passed 50.0. I didn't understand how that could happen.
Next semester, I was enrolled in Latin again. I decided to drop it. But I thought, before dropping it, I should just go to the first lecture. As I was leaving at the end, the lecturer pulled me aside. He said to me, "You know you failed the exam, right?". "Yes", I replied. Then he said: "Too many students failed, and the administration told us we had to give some of them passes. We liked you, thought you were really enthusiastic at the beginning, didn't know what happened to you, and are hoping you might continue the subject, so we decided you'd be one of the lucky ones whose fail gets turned into a pass." I thanked him for his kindness, but I still dropped the subject anyway.
It was an interesting insight into just how "flexible" university marking can be.