(NSFW?) What qualities influence how much you enjoy sex with a particular person?

I’ve had a couple conversations lately in which men said the most important factors for enjoying (heterosexual) sex are how enthusiastic the woman is, and how confident she is—her actual attractiveness isn’t so important.

I’m wondering if this is generally true, and if there are other factors that are important? I was initially curious about men’s preferences for women, but it should be interesting to hear from everyone about everyone.