Left vs right hand thread wheel studs.

It's incredibly sound and logical engineering.

...but most "people" are stoopid.

I think it's part of the character of our cars.

I used to have magnets in high visibility colors that said "CAUTION - LEFT HAND THREAD".

Now I only trust one other shop to do any wheel work and I've known them for 30 years.

(and I also have converted to RH since my LH stud source dried up)

A good 4x4 shop usually has LH stuff in stock, but ours closed up about 15 years ago.