I used to think that in reruns the actors were actual performing again. It never occurred to me to think why they never aged or anything.
A childhood belief about tv

others believed things like this
- last time when the television was on i thought the people were performing in it -.-
— irritated kid - I used to believe that the Fire Station was where all fires occurred.Anon
- When I was a little kid I thought that salt was some form of an aged sugar.— Jodie
- I used to believe that a 'Flea Circus' really was a circus with performing feas!— Jo Lancashire
- that actors went to the toilet during the ad breaks.— ash
- As a child I used to think that actors really died in movies.— Jordi Comendador