alt Hacker News> High graduation rates are an important metric to administrators. If a professor gave a failing grade to 1/3 of the class they would be in hot water.
I remember practically every single instructor/professor on the first day of class during my freshman year of my undergraduate study said something along the lines of "I have no curves. Your grades depend on you and nobody else. If the whole class does well, everyone can get an A. If nobody does well, everybody can fail."
So I guess this was more motivational to get us to study rather than stating facts?
It really depends on what kind of class it is, but at most schools:
* If 1/3 of calculus physics for engineers fail, they take it next semester.
* If 1/3 of gen-ed physics for poets fail, the professor better have a good explanation for the provost.
* If 1/3 of physics for pre-meds fail, the professor better have a pretty good home security system and might want to think about having the family stay in a hotel for a few weeks.