Why girls like the "bad boy" Pt. I

Excerpts from The Natural History of The Rich - R. Coniff

It's really relegated to nothing more than a vestige of ancestry in the modern human world, but in the natural world, there is a very clear cut answer to this puzzling question. Natural selection basically means that nature weeds out unfavorable traits by killing individuals that display them. Thus an arctic fox with a patch of red fur spelling the words "Eat Me" on it's his side would quickly end up in a polar bear's belly regardless of the bear's illiteracy. Whereas those with more favorable traits like plain white fur for camouflage in the snow will be more likely to survive and reproduce.
In most species, the females control the mating and most of the sexual selection, and they often have an irresistible attraction to the male with the "Eat Me" sign. That is, they seem to select males for traits that make them less likely to survive.
In peacocks for example, the upkeep on a big flashy tail requires the male to waste huge amounts of energy. It also inhibits his ability to fly and makes him more vulnerable to predators. The female's own drab coloration attests to her abiding faith in the value of camouflage, yet she will nontheless choose a male with a bigger showier tail almost every time.
To be fair it works both ways, for example small breasts are just as good as big ones for nursing babies, and in our ancestral environment flat-chested females would also have been better equipped for climbing trees and running from predators. But men like larger breasts, having them is of course a handicap, a cost ancestral women undertook to display greater nutritional fitness in the form of visible body fat in a desirable location.
Given the ruthless efficiency of the natural world, how could such costly displays have evolved in the first place?