One way to juice the economy is just print more money and give it to everyone. Everyone's richer, yay! Except you haven't increased production or necessarily consumption, so prices will just equalize to the new money supply and you get consumer price inflation.

For QE, we got smarter, and just gave all of the money to the bankers, because that's what all the economic experts who work at banks said to do. So all of the inflation happened in assets held by banks and rich people instead -- tradeable securities and real estate in coastal areas.