Quote from endsongs:
Any amount of sustained deflation might = economic doomsday. This is why the gov't is pulling out all the stops to create inflation. Believe it or not, there are millions of American businesses and households that have barely managed to survive the economic crisis so far without defaulting on anything. They want to maintain good credit so when things improve, they can take full advantage. If deflation causes those who are surviving, but on the edge, to start defaulting on their debts because of the increased relative servicing costs, then a chain reaction might happen to cause another depression. Not to say this will happen during the current recession, but the next recession, and yes people this is not the last recession the US will experience, will be harder to dig out from as so much was used to stop this one. IF we manage to avoid falling into a depression this time, it's very likely the next recession will lead to a depression.
Deflation must be avoided at all costs. Temporary deflation is OK but long term deflation is horrible. Nobody will spend money and the economy is stuck in pergatory perpetually.
Stagflation is also worrisome in the near future with the stimulus spending, but deflation is what the government is aiming to avoid currently.