No not really lol men can cum from anal alone, men can cum from spanking alone, some men can cum from nipple play alone. Its really all about the individual. (=・ω・=)
Maybe you need to game up your skills? :P there are techniques and workouts(kegel? to stretch some pc muscles) that requires few earlier sessions to master them. If they work let us know. I don't have the male physiology.
Just a reminder to ladies....men don't come when they are spanked on the ass.... it's just a yaoi theory. A dude can't just come without nut ok...