What is/are the worst thing/things you ever bought. Mine was an air conditioner that you added ice cubes to.

[NNadir]

9. My parents had one of those ice addition air conditioners and used it in my bedroom, which was over the kitchen.

My small 2nd floor bedroom growing up was the hottest room in the house.

Nobody in my house understood the laws of thermodynamics when I was in high school. When I learned the laws of thermodynamics, in particular how refrigerators worked, I was embarrassed and understood why I was covered in sweat every summer as an adolescent and teenager. (A refrigerator puts out heat; it's a heat pump that rejects the heat of cooling and freezing . Besides the heat of crystallization/fusion, the electric motor also generates heat.)

The worst purchase I ever made as an adult was a new 1994 Mercury Sable. It was, without question, the worst car I ever owned, and I owned a large number of cars.