From the great Milton Friedman:

There is hardly any view that is more widespread than the view that somehow or other the Great Depression was produced by a failure of private business…

The Great Depression was produced by a failure of government, by a failure of monetary policy. It was produced by a failure of the Federal Reserve System to act in accordance with the intentions of those who established it. It was produced by a failure of the Federal Reserve System despite the presence of knowledge on the part of many of the people in the system about the right course of action. It’s interesting to speculate for a moment about why this myth is so widespread. The answer is really very simple in this case.

Private enterprise has no press agents. The free market has no press agents. The government has a great many press agents. The Federal Reserve has a great many press agents. And the Federal Reserve, of course, would never admit, never proclaim that it produced the Great Depression.

What Friedman left out was how the Smoot Hawley tariff and then massive tax increases under Hoover and FDR’s failed New Deal also helped turn a temporary financial crisis into a 12-year Great Depression.