People consume cars, computers, and phones; the primary intent is to use the product. You might sell it used at some point, but that's not the primary intent, and you're almost certainly going to take a loss on resale.

People invest in companies, governments, and individuals; the primary intent is to provide a loan that will be repaid with interest.

A physical object could be considered an investment, but only if that object is rare or somehow naturally limited (e.g. real estate).

So with inflation, you're rewarded for making investments, because otherwise your money will lose value sitting in fat stacks under your mattress. With deflation, you're rewarded for keeping those stacks hidden away, because it's a risk-free way for it to gain value.