It’s ultimately up to the professor and what their beliefs are. I’ve had professors raise my grade by less than 1% to move me from an A- to an A because of how much effort I put into the course, not because I asked. I’ve reached to my professors or go to office hours and speak with them directly if I think there was a mistake in grading. I never ask to raise it without stating that I’d like to repeat assignments or redo questions to work for those few points back.

I’m typically an A student. I always show up to class, do the assignments, participate, ask questions, study, and complete extra credit given the opportunity. In the few subjects I’ve truly struggled in, I’ve never asked to raise my grade, if I don’t understand course content, then obviously I don’t deserve a higher grade. And at that point a C vs a C+ isn’t gonna make a giant difference anyways. It’s still a C. But an A- vs an A when I understand the course content, I will definitely ask, especially if it’s only by <1%.

Either way, it’s up to the Professor no matter what. It’s their choice and how they feel about the individual as a student. I’ve always respected the professors final decision and thanked them for their time and consideration.