My first thought is it would be something like this (https://radiopaedia.org/articles/chauffeur-fracture?lang=gb) . According to radiopedia, that fracture came from the crank handle, of an old fashioned crank start car, reversing and impacting the dorsum/ back of the wrist. Additionally they use terminology, e.g. dorsiflexion? instead of extension, and abduction? instead of radial deviation which is a bit different than I was taught, and taught to others. Tho' that mechanism doesn't seem to be what I recall from school. In the off chance that I'm correct, as I recall the fracture occurred when one wrapped one's thumb around the crank handle, such that when the engine started the thumb would provide leverage against the radial styloid process. I've met people who own such antique cars, and have never heard of any of them making this mistake. So to answer your question, it's not random, few things actually are. It's the radial styloid.