Did you know that in the United States, there are 5,000 janitors who hold a PhD? I didn’t know either until I stumbled on this post on Quora. The most popular response comes from Joseph Wang, PhD, who posits two credible explanations:
3) I’ve known people that have worked as janitors, and they say it’s an easy job. You get paid eight hours of wages for work that usually only takes two or three, and you spend the rest of the night just chatting. You work in the middle of the night so your manager isn’t going to be looking over your shoulder, and as long as everything is clean the next morning, no one cares how many hours you “really” worked.
4) You can do janitorial work and theoretical physics at the same time. You are pushing a broom, you can think about quantum field theory. This is *not* true for a lot of other jobs. You can’t think about QFT while taking orders at McDonalds, selling shoes, flipping burgers, or driving a cab. If the janitor has a blank vacant look, no one cares, whereas being absent-minded while dealing with hot cooking oil or customers can get you fired or cause a fire.