When sex is good, it's great, but when it's not so good, it can be hard to even pay attention. You're supposed to be caught up in this epic, all-consuming moment, but instead you're trying to act enthusiastic and on the inside you're all like, "Are we done yet?"
Condoms allow for folks to not only avoid pregnancy and disease, but also to have a great place to store semen. Unfortunately, that's not the end of the problem.
70% of women have faked an orgasm at least once, if not multiple times. Clearly, many women are not having a great time in bed, and are so eager to get it over with they fake it to be "finished already."