1. Some women are like cheer-leaders to their husband, supportive in times of crisis. Also like one on bed. Their husbands are fortunate to have them and hope their men are good to them too.
2. Some women are demanding and marry their husband for $$$. Men who married them are blind. Those left on the shelves didn't manage to con any rich prospects.
3. Some women are not submissive or demure. They are not after $$$ but their attitude scare men away. Those left on the shelves didn't manage to find any beta-husbands.