This is totally right. There are two kinds of classes: those with a specific set of learning outcomes to meet (eg. a prerequisite course) and those where by the

This is totally right. There are two kinds of classes: those with a specific set of learning outcomes to meet (eg. a prerequisite course) and those where by the end the in-scope knowledge is essentially unlimited (eg. courses where it's not unreasonable to prove named theorems on homework or exams). The former should be graded with 100% being all the knowledge, the latter in a way that gives a fair distribution and then scales. Of course, my fellow university students always push back on me when I support the latter :) At the risk of armchair psychoanalyzing, I think a lot of them don't want to reckon with the fact that there's such an overwhelming amount of information out there and so many perspectives to explore it from that "100%" in say introductory topology is almost completely meaningless as a measure of how much topology one actually knows.