Oh I believe any class you failed wasn't your fault. I was goofing off, and hated the class. History is a weak point for me. I like historical context and historical ideas, but I am lousy with names and dates, which makes me particularly weak on history tests ;~D
I had some bad classes! Got a couple Bs that should have been As, if I'd really studied. One of my two Cs could have been a B... but I learned a lesson about goofing off. And about how to study.
History was never an issue for me. I just read a lot in high school, then when I got to college everything was watered-down pap. But dates were hard. And trying to keep Louis XIV and Louis XVII straight... no, thanks.