The whole marriage proposal is analyzed and compared to an auction and then game theory is applied to come to the conclusion. Lets chuck the technicality and talk in basics. In a classic version of the marriage proposal: A woman makes it known that she is open to a proposal, the man proposes, and the woman chooses to say yes or no. The structure of the proposal is not, "I choose you." It is, "Will you choose me?" A woman chooses to receive the question and chooses again once the question is asked. This may not be true in India but it probably true for our generation to some extent.
Now you would think that since the power of choice lies in the hands of women, strong and confident women (strong bidders in the auction) would get to pick the best men and weak women (weak bidders) would be left alone. Here's where game theory says that it's actually the other way around. Game theory predicts, and empirical studies of auctions bear out, that auctions will often be won by "weak" bidders, who know that they can be outbid and so bid more aggressively, while the "strong" bidders will hold out for a really great deal. You can find a technical discussion of this here. But you can also see how this works intuitively if you just consider that with a lot at stake in getting it right in one shot, it's the women who are confident that they are holding a strong hand who are likely to hold out and wait for the perfect prospect. And while the weak bidders, lure men in their womanly ways!!
So at the end, what is left is a below average male population and an above average female population. Here's the best line in that study:
Where have all the most appealing men gone? Married young, most of them—and sometimes to women whose most salient characteristic was not their beauty, or passion, or intellect, but their decisiveness.
Now let me put in my personal touch. Why are men so stupid? Why is it that "strong bidder" men succumb to the worldly wiles of "weak bidder" women and not hold out for a woman to match their "strong bidder" type characteristics? I had this theory that men somehow don't evolve as much as women. They somehow don't understand that marriage or getting "settled" has long term implications. As liberated women, we think of work home balance, independent incomes, broad minded outlook towards life and other suchlike attributes which contribute to a quality life. But men don't seem to have come out of stone age, where only criteria is that women would give birth and look after offsprings' and his own needs. For a long time I couldn't understand why men seemingly cant understand this and evolve according to changes in society; until one day when I was discussing with a friend, I popped the question, "why are men not open minded?". I got a reply which shook me, "its cos they don't need to, women NEED to be open minded to be able to do things to fulfill her own ambitions, but men can do that even without being open minded! That's society!!" So simple and it never occurred to me. I never thought from a man's point of view.
Well so much for the depressing theory. But there are some exceptions to every theory I guess, there would be certain "strong bidder" lucky women who get their men; and also certain "strong bidder" type men who hold out. So girls, go find the one who is worthy and then bid with all your heart!!