I'm a college professor, and I constantly tell students that grades don't matter... it's the knowledge that matters. E.g. learning things that make you wiser shouldn't depend on whether those things are on the exam. ...and most students still care more about getting grades than actual knowledge.
I have to question your approach in creating the exam if students with the knowledge are unable to get good grades at it.
If students who got the actual knowledge cannot get good grades, the problem is YOU.
How about turning this around, and have your college constantly tell you "Salary doesn't matter, it's doing great research and great teaching that matters!", and then give you great research facility and students, but only give you minimum wage while awarding great bonuses to management. How many professors would care more about getting better pay than actual knowledge?
What? Who said the students with knowledge don't get good grades?
GP is talking about students who don't have full knowledge but still get good grades, because all they care about is targeting the exam.
Then they forget about it, and leave with the piece of paper but no actual learning.
(I'm extrapolating here, anonymous prof, based on my own experience; I don't mean to put words in your mouth.)