Steven Randy Waldman writes,

A housing boom, any kind of boom, is attended by an increase in certainty. Information is stimulus, confusion is contraction. A bust occurs when the market is unsure of everything, when market participants perceive better risk-adjusted return in holding government securities (or supply-inelastic commodities) than in financing real investment. Sectoral shifts per se have no clear implication with respect to variables like employment and output. But “hangovers” do happen, because powerful booms are periods when market participants make consequential decisions with great swagger and confidence, and busts are when we learn that despite their certainty, they were wrong. They are left not only impoverished and burdened by debt, but bereft of confidence in their ability to evaluate new opportunities.