https://blogs.scientificamerican.com/observations/how-wrong-should-you-be/
Cody Kommers claims that “If you always get 100 percent on your tests, they aren’t hard enough. If you never get above 50 percent, you’re probably in the wrong major.”
However, the incentives created by competitive admission gateways to college, entry-to-major, and/or graduate/professional school may be misaligned with the idea that optimal learning occurs at a difficulty level where students get some problems wrong, but not too many. I.e. students have incentives to choose the least challenging (“easy A”) paths that are not blatantly obvious as such, rather than choose the appropriate level of challenge for optimal learning even if it means less-than-highest-possible grades or GPA.
Of course, a student doesn’t get to pick how her professor makes tests. If she is aiming for 85% but her professor expects most students to get 100%, she might fail, and if her professor makes hard tests where the best students 50%, then she might erroneously avoid a class she would have learned a lot in.
It sounds like the advice here is for the student to aim to be in the middle of the curve for tests, challenging herself but not taking classes where she is hopelessly out of her depth.
The best engineers are the ones with the biggest string of failures early in their career. The mantra is, “Fail fast, fail cheap.” It hones the innovation instinct.
That 85% rule probably applies to other fields as well. Failure forces new ideas.
This is why grade inflation is not a good thing for any school and its students. Surprisingly, some of the best schools in the nation are the ones with the most grade inflation.
I may be weird, but I still remember more of the questions I got wrong - even back in high school - than questions I got right.
I often remind students that getting something wrong is sometimes a favor for them in the learning process - as long as they put in the effort to learn what the right answer was and don’t just shrug it off not caring. Of course, one can also do that with HW so one has better chances of doing well on a test, but it applies across the board.