system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does the price of everything keep going up?
gpt
Central banks, more or less, have control over how much money is in circulation and also have a fairly good idea of the amount of stuff produced and services provided. As such, modest inflation, and thus increasing prices, is a policy choice.

The reason why is that it incentivizes investment (why hold cash instead of spending it or lending it to someone with a productive use for it if it will decline in value over time?) and helps avoid deflation (decreasing prices), which creates a feedback look sapping investment and spending (why spend your money now when it will be worth more later?).