Everyone is different. As a guy, I like to start slow and then build up. At the end, right before and during orgasm the body goes on autopilot and I go fast and hard. My DW's favorite approach includes a fair amount of foreplay, leading to my manually stimulating her to the point that she is just starting to come, then she wants me to penetrate her and pump her like a jack hammer while I continue to manually stimulate her clitoris. When she wants me inside of her, she definitely wants it as hard and as fast as I possibly can. Of course I love it, but I would usually prefer to start slow then build up the rythmn. So it's not always a guy thing. Sometimes it's a gal thing as well.