Why can't companies figure out scale?

[JennyC6]

This issue bit me pretty bad with my CA-10. They advertise it as 1/12 scale, meaning a normal height person would be accurately represented by a six inch figure. So I bought a Duke Nukem action figure for use as a driver....only to find Duke's about 30% too tall to fit in the cab without sawing him in half! I'm thinking it's really a 1/14-ish like all the Tamiya trucks and that I need a 4.5-5 inch figure as a driver, rather than a six incher.