When disillusion falls upon an overoptimistic and overbought market...!

It is of the nature of organized investment markets, under the influence of purchasers largely ignorant of what they are buying and of speculators who are more concerned with forecasting the next shift of market sentiment than with a reasonable estimate of the future yield of capital-assets,that, when disillusion falls upon an overoptimistic and overbought market, it should fall with sudden and even catastrophic force.
~ John Maynard Keynes, Chapter 22,The General Theory

When disillusion falls upon an overoptimistic and overbought market...!