I've heard several theories for why inflation occurs, but one in particular fascinates me: expectations of inflation can themselves create inflationary conditio

I've heard several theories for why inflation occurs, but one in particular fascinates me: expectations of inflation can themselves create inflationary conditions. If everyone expects prices to rise, it's easier for companies to justify price increases without too much risk. It's similar to the situation where companies may collude to raise prices, except this requires no coordination or ill intent. General expectations automatically coordinate behavior. I wonder how much of an impact this would have compared to actual supply chain issues, increased money supply, and low interest rates. My expectation is that an efficient market would not permit this, since a single company could lower prices and succeed, but every market has inefficiencies.