It’s a slow day in some little town… The sun is hot… the streets are deserted. Times are tough, everybody is in debt, and everybody lives on credit. On this particular day a rich tourist from back west is driving thru town. He stops at the motel and lays a $100 bill on the desk saying he wants to inspect the rooms upstairs in order to pick one to spend the night. As soon as the man walks upstairs, the owner grabs the bill and runs next door to pay his debt to the butcher. The butcher takes the $100 and runs down the street to retire his debt to the pig farmer. The pig farmer takes the $100 and heads off to pay his bill at the feed store. The guy at the Farmer’s Co-op takes the $100 and runs to pay his debt to the local prostitute, who has also been facing hard times and has had to offer her services on credit. She, in a flash rushes to the motel and pays off her room bill with the motel owner. The motel proprietor now places the $100 back on the counter so the rich traveler will not suspect anything. At that moment the traveler comes down the stairs, picks up the $100 bill, states that the rooms are not satisfactory, pockets the money & leaves. NOW,… no one produced anything…and no one earned anything…however the whole town is out of debt and is looking to the future with much optimism.

That version from here: https://www.econlib.org/archives/2012/01/an_answer_to_a.html

Something something velocity of money something I never took econ 101.