This is a pretty good description of it:
A market’s logic can serve us well when its evaluation of costs and benefits comes close to matching our own, but it can also fail us when the two diverge. In some cases, it can relieve us of thinking too hard about coordinating economic life. In others, it can produce results that are perverse, as in health care. But like computer software, when a given program fails to serve its users, there is nothing unnatural about revising its underlying code. The same could be said for the laws that underpin a market.
A market is a social tool; it is a means, not an end. Mistaking a mechanism as a virtue in itself is morally deranged. Consider, for example, Ron Paul. During the Republican primary debates, Paul refused to judge our market for health care by how well it served the sick but poor. Instead, he admonished us all to contort ourselves so we may fit the righteous device.
Why are free markets the best? Because they are the best. What part of that don’t you understand, libtards?