This is a good read, and very true as I have discovered while dating. To those women in their 20's who feel they can pick anyone they want, pick someone now, when you get to your 30's there are far fewer choices.
http://ozconservative.blogspot.com/2009/07/missing-out.html This had significant consequences. It meant that women no longer favoured family men. Men were rewarded for being unsuitable in some way. So the attitude of men changed as well. Some adapted to the culture of casual relationships by becoming players. Some withdrew from the whole dating game and adapted to a lifetime of bachelorhood. Some looked elsewhere for women. The result was that when some of these middle class women did finally start to look for husbands they met men who were no longer as keen to commit.
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Women in their twenties are in a strong position. They are at the height of their desirability to men. The danger, perhaps, is that this makes them feel "invincible". They may not realise that their advantage won't last forever and that it's most sensible to find a partner when the going is at its best.
Why else doesn't the autonomy principle work well in real life? It's not just that men prefer feminine women, but the biological reality of a woman's ticking clock: