So I'm trying to understand how sexual selection was evolved. The current understanding seems to be females in most species are the choosy sex and males must either impress them or beat the shit out of each other to get access to them.

But on the other hand males also just use this selected size/strength advantage to subjugate females and advantage the more submissive ones / coerce / abuse the ones that are "out of line" or try to leave his harem / kill the offspring of other males.

So who is actually driving sexual selection? Males or females?