But inflation isn’t a problem, it’s a benefit. We want people to spend or invest (in production) their money; economy works best when money is actively circulat

But inflation isn’t a problem, it’s a benefit. We want people to spend or invest (in production) their money; economy works best when money is actively circulated, not hoarded. The problem with a totally fixed money supply is that as productivity grows new investments are disincentivizes, as a fixed currently holder get the benefits of aggregate productivity increases (through deflation) without risking his money in investing in companies.