According to Bryan Caplan, "our [higher] educational system is a big waste of time and money." He is writing a book about this -- yay! He attended college at the place I know the most about -- UC Berkeley. Here is why it is a big waste of time. Professors can only teach what they know. All they truly know how to do is how to be a professor. At a research university, that mainly involves doing research. Berkeley professors can teach how to do research, sure, but that has little to do with what most Berkeley students will do after they graduate. So a lot of time is wasted. It is most unfortunate to (a) require all students to imitate professors and (b) to rank them according to how well they do so.
In response to Caplan, Catherine Johnson says her undergraduate education was useful. But she became a nonfiction writer -- very close, in the big world of work, to what professors do. That's one of those exceptions that prove the rule.
I think practically everyone learns well if any of three conditions are met:
1. Apprenticeship. You want to be good at doing X, you will learn by watching someone skillful do X. Effortlessly.
2. Guru. If you think of so-and-so as a guru, you will learn from him or her. Effortlessly.
3. Stories. Stories teach values. Things associated with the hero become considered good and desirable; things associated with the villain become considered bad and to be avoided. Effortlessly.
Most university classes, however, fulfill none of these conditions. On the face of it, university classes teach; but crucial details are missing. It's like butter and margarine. Margarine is supposed to be as good as butter but it's not. There is a superficial resemblance but margarine lacks crucial vitamins that butter contains. Because university classes lack crucial elements, they are forced to use grades, tests, and fear of failure as motivation. These motivators don't work very well, as Alfie Kohn among others has pointed out. Sort of for the same reason Humpty-Dumpty couldn't be put back together again.