I've no idea of economics. But I lived in a country where for a decade we had deflation. Let me tell you: not a good thing! At the beginning, seems good, each time you buy something, is cheaper as before... but that has the down side: people start to speculate: they do not buy what they need, they wait until the very last moment. Moreover, the money in the bank, is a good thing, each time it is more value... so "don't spend". May seem a little thing, but when the whole economy goes in that train, it starts to stop everything, which in turn makes more deflation... you get the idea.
It was explained to me, at that time, that a little bit of inflation is a good thing, and keeps the wheel turning.
Maybe somebody who really knows about economics may laugh...