Do you ever get up in the morning, head to the bathroom, take a nice deep breath and proclaim, “Gee, I’m sure glad my bathroom doesn’t smell like shit!”
Of course not. Because as an American, you live in a country where bathrooms only smell terrible after someone has recently defecated.
What you may not realize is that most of the world isn’t so lucky. In fact, even modern European countries have bathrooms that smell absolutely terrible at all times. The smell often noticeably makes its way to the rest of the building, and I say this as someone who’s hard of smelling.
So why is America different? IT’S A TRAP!
Ever since British plumbing guru Thomas Crapper invented the U-shaped “trap,” pretty much every sink drain in the US has used his design. Go look under a sink and see for yourself.
The purpose of this invention is to contain a small amount of water in the U section that air cannot escape through. This prevents foul gas from the sewers from rising into your house and making your bathroom stink.
For some reason in much of Europe, Mexico, etc. the trap never gained much traction. Instead, people prefer to save a couple bucks on plumbing (see above photo) and pretend that the disgusting sewer smell is normal.
There’s plenty of things I’ll never understand about the rest of the world. This is #1 on that list.