The markets have not some in-built mechanism which can prevent them from ending in self-destruction. They need to be regulated. Markets are like fishermen in a pond, who try to catch as many fish as possible. If you don't regulate them, there would be no more fish and fishing soon.
Discussion
Who do you expect to regulate the market?
The state of course, but that's where bad things can happen. It is true that the state tends to be corrected. Corrupted by corporations of course...
The state is a monopoly of a region. That is the problem. A single regulatory body that is, and will always be corrupted because its a monopoly you have to use. That's the big problem we need to solve.