If you are making love to your woman with only the intention of pleasing yourself, it is not going to be as good—however—if you instead had the objective to please her first and you second, not only is it going to be a hundred times better for the both of you; she's going to crave more, and more, and more. This will also overall improve your relationship.
So in short; If you want a great relationship and even greater sex, put your partners pleasure first and yours second.