@BasedLunatic
The best explanation I've heard comes from women MRAs.
Basically, women are and aren't lying about this. When they're single, they're more likely to pick the guy on the right for a fling, a sexual escapade, whatever you want to call it.
But if they're in the mindset of settling down, when they think about someone they want for a long term relationship/marriage, they will pick the guy on the left, who is still decently fit, but looks like he'll do other stuff with his life other than lifting weights, so he's more likely to be a good provider.

It's basically a rehash of the old alpha/beta male thing. They'll fuck around with the bad boy "alpha", until they decide they want to settle down, at which time they pick a "beta" that is loyal, will provide for them, that may even raise children that aren't biologically his.

Something else to note, which I haven't seen anyone address yet, women's preferences change if they're on the pill. This has been studied. And I suspect it would influence women's behavior into picking the guy on the left, because the pill essentially tricks their body into thinking they're pregnant. So hormones are gonna force them into the "I need to settle down" mindset.