For the same reason the market will miss its highest gain, because it can only see to the short term goals. There are many problems with capitalism, and I think that socialism is the best way to solve them. Note that socialism is not marxism, is not dictatorship and does not require that market economy is removed. In recent times I have more and more come to like the idea of Syndicalism. For those of you who don't know what Syndicalism is, here is a little description of the parts I like.
Syndicalism is against centralization.
Small self-running units will give the workers greater democratic controll over their works, and will decrease alienation. The units are owned by the workers as a cooperative, and all descisions are made by worker-councils. Interestingly enough, similar ideas of company networks are very popular today among company leaders. Unlike Social Democrats and Communists, Syndicalists are men of action, not politics. Syndicalism is not aimed at taking controll of the state through elections or revolution, but to eat up capitalism from within.