The Happily Never After.

I got to thinking while washing up this evening, about one night stands. Or more specifically the relationships that we choose to have. Someone once told me that we all have exactly the relationships that we want (either by default or by effort.) So that got me to thinking: how do they decide? What makes someone a "one night stand" candidate?
Being that I have an ever growing circle of guy friends (because I am generally seen as being a dude with boobs) I have sat in on some "shop talk" about the "ladies from last night." Now, some of these guys are generally charismatic sons of bitches who could talk their way into just about any one's pants, but they choose. Darwin at work perhaps? Maybe that girl just reminded them of someone they wanted to nail in high school... who knows. I don't really see this as them scraping for sex, but the itch must be scratched. Enter Females. Let's say we are all sitting at a bar, not necessarily trolling for tail, but surveying the spoils. One has to wonder, how much are they willing to let slide for their one night stand? Can she have one leg that is shorter than the other, or must she be the next Giselle? Where to set the bar?.. this is what I wonder.
Given the fact that the male sex drive tends to be pilot, eventually they opt for a lady of the night, in fact I think they would prefer it. The ladies are sent packing shortly after orgasm, never to be seen again. Most girls are looking for the fairy tale with the prince on the white horse who is ready to sweep s away to a castle on the hill, and in order get off a shot, the men must pretend to have some saddle skills. But that still doesn't answer what makes someone worthy of a one night stand.
So what is it? You tell me. The T&A isn't enticing enough for a second showing? Boring as a box of rocks? The grand tour not live up to the brochure? Just need a little dirty romp? Maybe it is just bad timing, but in the mean time, I can spend MY time with him/her? Endless possibilities. But the "tail" ends with a happily never after.