Another weird observation is the flush performance of European toilets. They don't clog up:
https://www.hunker.com/13400906/what-is-the-difference-betwe...
Flush Performance Most American toilets use siphoning or sucking action to forcibly draw the used toilet water through toilet trap and into the attached sewer plumbing. The neck of the toilet hole is small enough to facilitate suction, a design choice that often necessitates the use of a plunger in the case of a clog. European toilets typically utilize a washdown flushing system in which water inside the toilet is forced out through water flowing from the rim of the bowl. The neck of the toilet hole tends to be larger so there is less of a chance of clogs, but the bowls may require more frequent cleaning from any leftover residue.