The hidden purpose of all female fashion and the "beauty industry" that supports it -- namely, to help to generate male erections. Sometimes abbreviated to "the H.O. Factor," it is what some feminists treat with disdain and attempt to subvert by refusing to wear make-up. Every fashion designer, male or female, recognizes its importance, however, as, instinctively, do all heterosexual women.
She: I looooooove the new Chloe collection, especially those floor-length dresses and baggy blouses with long sleeves!
He: But they completely lack the H.O. Factor.
She: The whaaaat??
He: The Hard-On Factor: they are absolutely NOT arousing ... not even a twitch ....