Socially natural competition perhaps but I dont believe them to be natural laws.

I don't want to reduce attraction to scores of successes and failures.

"A man is worth having if multiple girls agree that man is worth having.
A girl is a success if she beats several girls who are after the same man."

This does well to explain a girl that trades sexual favors for pretty shoes as OP suggests. Okay,

"Settling for a man whom no other girl wants is a failure"

Not for that man certainly and the girl could be pleasantly surprised. So I dont think of this as a failure naturally.