This is really interesting to me. I was caught in what was retrospectively a very unpleasant relationship with a narcissist recently and after the discard phase I thought we'd got back together because, well, it seemed like we had. The last time I saw him, he fucked me in a very unrewarding way for about two minutes and then rolled over and went to sleep.
A few days later, when he told me I wasn't his girlfriend again yet because I still wasn't forgiven, I remembered that duty sex and the scales just fell from my eyes. It seems like my vagina has better boundaries than my brain. 😅
I don't think performance can be managed to the same exceptional quality each time, and in relationships I am willing to tolerate the occasional rubbish shag, but I have a high libido and if I'm showing you my vagina without girlfriend benefits, you'd better show your gratitude.
I don't know how much this contributes to the discussion. When I was married I actually ceased all sex with my husband because I never enjoyed it with him.
Germaine Greer said, bad sex is bad for you.