The fairy says « I will give you what you most desire if you do someone else’s job for a day. »
The professor says « I’ll be an elementary school teacher. What can be so hard about teaching a bunch of 6-year-olds how to read? » so he is teleported into a classroom. After a few minutes, all the kids’ screaming gets to his nerves, so he throws all his supplies and gives up.
The C.E.O says « I’ll be a waiter. All you do is carry food back and forth. This’ll be a breeze » so he is teleported to a restaurant. After about an hour, all the annoying customers drive him insane, so he smashes his plates on the ground and gives up.
The janitor says « I’ll be an artist » so he is transported to an art facility. He glues all the classroom supplies and shattered plates to a canvas, then sells it for a billion dollars. The fairy asks the janitor how he was so clever.
The janitor says « I got a masters degree in art. »
Edit: Thank you for the silver, gold, and platinum!