Why do some watches using Roman numerals choose to use IIII for the number four rather than the correct IV?

Answer 1

While IV can be seen as a simplification of IIII, one reason that IIII is used instead of IV is - if you look at the watch symmetrically - with a line down the center - VIII and IIII appear symmetrical to each other and thus IIII is seen as being more aesthetically pleasing than IV.

Legend has it that the Romans themselves would have used IIII instead of IV because the letters IV were also in the name of one of their Gods. This is probably apocryphal since subtractive notation was introduced in the Middle Ages, long after the fall of the Roman Empire.