Obviously this is highly speculative but for quite some time now I have the theory that the former Sowiet Union states (Russia et al) and large parts of Latin America don't progress as much simply because male financial success isn't tied as much to better dating options. At least to me as a traveler it seems that many men in those countries have a wide choice of attractive girls, regardless of how well they are off.
This would also explain the rise of the Chinese economy in the recent decades, as they have a surplus of men and I heard that they need to own at least a flat and a car to have chances on the dating market.