The world has a lot of different standards for a lot of things, but I have never heard of a place with the default screw thread direction being opposite.
So does each language have a fun mnemonic?
Photo credit: https://3.bp.blogspot.com/-Giy8OrYJTjw/Tfm9Ne5o5hI/AAAAAAAAAB4/c7uBLwjkl9c/s1600/scan0002.jpg
We used to have one: “Solang das deutsche Reich besteht wird jede Schraube rechts gedreht.” (“As long as the German Empire persists every screw is turned right.”)
Given that the German Empire failed spectacularly, this sentence isn’t very popular anymore.
I know it as “Seitdem das Deutsche Reich besteht wird die Schraube rechts gedreht” (“Since the German Reich was founded, the screw has been turned to the right”), I always assumed it was because many things were standardized between the German states after unification and that was one of these things, but I can’t find any reference to that.
I have never heard that before this thread, possibly because I was born in Austria decades after the name “Deutsches Reich” was abolished.