From a biomechanical standpoint, the female orgasm is simply a part of reproduction that improves the conditions needed for the male sperm to successfully travel to its target.
The male orgasm generally takes the send out millions to the front lines pronto knowing that it'll be lucky to have even one survive the trip.
I guess it could have been designed to have smaller moar frequent incursions to accomplish the same task.
But, it don't be like it is that way for some reason much to the dismay of many such men.