STEM exams can have partial grades based on the completeness of your answer. They were rarely simple right/wrong multiple choice tests. And it was those where I ran out of time, and I hated the fact that I didn't even get to answer some questions because of this fact.

Edit: And some exams deliberately had more tasks in them than what could reasonably be answered in time, so you had to optimize by seeking out the high scoring questions first.

The more I think about it, the more I realize just how much of my higher education was only about gaming the system and not actually learning anything.