The thing is that both inflation and deflation are GOOD but also necessary for an economy to grow.
Just as we all say, too much of anything is not good. The same applies here.
Think of it this way. Inflation increases purchases which is good for the overall economy. It basically makes us feel that we'd better spend NOW because in a week all our money is going to be worth a lot less. This will give government more revenue and ultimately grow the economy (support local businesses and everyone you'd expect with massive buying). However, inflation decreases consumer purchasing power. If you have $500 and the inflation rate of that currency sky rockets, it'll say $500 but will soon be worth a lot less thus decreasing your capabilities of buying anything.
Now, as you said, deflation is good too! When consumers have NO purchasing power and all their money is worth nothing, deflation will correct that. It'll give power right back to consumers and make us feel more comfortable. But, and this applies when trading commodities too, such as Bitcoin, why sell NOW (so buy something, say a house or a tv) when in a week it'll be worth a lot more? And that is what goes through someone's head when deflation occurs thus limiting purchases which decreases government revenue, decreasing spending and funding and ultimately killing businesses.
So each are good and bad in their own way. A solution? A little bit of both. Increase consumer spending while soon increase consumer purchasing power. Both of these things are vital. If inflation kept happening, with no deflation, our economy would go in the dump. Same applies for deflation.
Obviously no 100% cure for both, you're going to be stuck with them no matter what you use, but if you want to avoid government controlled inflation just use Bitcoin. The price is rising and you're a lot safer than in the realm of printing thousands of dollars everyday (which would always limit deflation, allowing infinite inflation KILLING the economy).
Hope this makes sense
