The most important asset a woman brings to a relationship, and which a man has an animal desire for, is sexual access to her body.

The average woman has a considerable advantage over the average man in that nature builds into the average man a greater desire for sexual activity. Consequently the average woman will receive more sexual attention (come ons, glances, etc) than the average man. However, nature doesn't allow women to keep this upper-hand forever: It gives women a number of years (and no more) where they'll be attractive to the greatest number of men they could possibly be attractive to. After this period, the woman is attractive to fewer and fewer men each passing year.

From the ages of 15 to 20, a young woman, on average, is getting more and more attractive. She stops getting attractive at 20, and maintains those looks (if she didn't have any children) for possibly 5 years. And then a gradual decline happens after age 25. Each passing year, she grows attractive to fewer men, until she's in her 50s and basically sexually invisible to nearly all men save perhaps the one who committed to her in the heyday of her youth and attractiveness (the husband she married 25 years earlier). The husband will have "wife goggles" for her because her younger self will have been imprinted on his mind. He will never have trouble seeing the younger woman. However, other men will only see the aging near menopausal woman.

This is why its important for women to make use of their sexual capital and marry early.

The price that women pay for not being burdened with being the ones who have to initiate relationships/make the first move etc is that later on a woman's physical quality degrades such that no one really desires them physically.

Women have an instinctive understanding of all this, which is why they're always limiting the subset of men who they would date to the subset of men who could POSSIBLY find them attractive. For instance, a 42 year old woman will consider dating men in their 40s and 50s, but she won't consider dating men in their 20s or 30s. That's because she knows that for those younger men, she would be competing against late teenagers and women in their 20s and 30s. So she rationalizes her (reasonable) calculation as being a consequence of desiring someone with equivalent/similar life experiences/maturity etc when the reality is that she's simply setting her sights on what she can get.