I admit I was never keen to do A levels in the first place but my (at the time) chosen career required at least two A levels, which I just got. It didn't help that I wasn't enthusiastic but I was one of those pupils that didn't really excel at anything. Apart from English Literature, where I gained an 'A', all my O levels were grade B. I'm still amazed I got Maths O level, having failed all my other Maths exams hitherto as I never found the subject that easy. I found the sciences less arduous but one of my science teachers advised me against doing any science A level, which I probably should have ignored. In the end, I took Geography, Economics and History plus General Studies. I completely failed Economics and History which was down to a combination of my utter indifference to both subjects plus absent and/or incompetent teachers. I scraped an E in Geography and gained a C in General Studies.
I didn't get to follow my chosen career but that, I admit, wasn't down to my lacklustre A levels but rather my performance at interview which fell slightly short of what was required. Nevertheless, I feel my A level years were wasted and I'd have probably been better off doing more sciencey stuff and steering clear of arty subjects. For context, I took my A levels in 1989 when there wasn't the variety of subjects and options on offer that we now have.
BTW, my Economics teacher was utterly useless (only two of our class passed, everyone else failed). The other class taught by the Head of Department all passed. Go figure. As for History, in the second year of study, we only had one lesson a week when we should have had four. Again, widespread failure. I admit I was by no means blameless but the teaching provision left much to be desired. No such problems with the Science and Maths teachers. Hey ho.