http://en.wikipedia.org/wiki/Deflation

Nobel laureate Friedrich Hayek, an Austrian Economist, stated of deflation during the Great Depression:
I agree with Milton Friedman that once the Crash had occurred, the Federal Reserve System pursued a silly deflationary policy. I am not only against inflation but I am also against deflation. So, once again, a badly programmed monetary policy prolonged the depression.
Interview with Diego Pizano (1979)[23]

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They are therefore rewarded by holding money. This "hoarding" behavior is seen as undesirable by most economists, as Hayek points out:
It is agreed that hoarding money, whether in cash or in idle balances, is deflationary in its effects. No one thinks that deflation is in itself desirable.[24]