[bff]

I've heard arguments to the contrary, for example that deflation encourages people to invest their money under their mattresses. If money you hoard loses value then you feel a stronger need to invest it, which is better for the economy as a whole. Without that incentive once a person reached some level of wealth they would sit on their money instead of putting it into a nice retirement fund that puts it into the stock market.

[dantheman]

It could perhaps be restated that deflation causes people to invest their money wisely and weigh the risks and rewards, whereas inflation causes people to chase rewards just to maintain their current wealth or underestimate risk to try and grow their investments.

Inflation fundamentally is just stealing from people by devaluing their earnings, and it hurts the poor and the middle class the most. It encourages people to take on debts, since they will pay back less in the future. It also hurts anyone who gets paid by the hour or salary when they're not tied to inflation.