IIII is traditionally used on clockfaces to distinguish it from VI and to keep the numbers "facing" in the right direction.
"To more easily distinguish IV from VI" makes more sense than any other explanation I've heard, but ...I've also heard that "IIII" was used because "IV" are the first two letters of Jupiter, king of the Roman Gods (i.e. spelled IVPITER in Latin), and so it was somehow disrespectful to put Jupiter's "initials" on a clock - but I kind of doubt if that was ever a true reason. Does anyone reading this know if it might be true?And I've also heard that "IIII" was used just to mirror the "VIII" on the other side of the face, because the clockface looks aesthetically unbalanced if you use "IV" there instead. This seems like a bit of an odd justification. though. Either way, I've definitely seen clocks use both "IV" and "IIII"...I think I like your explanation best, Anonymous.
What, no second hand? What a rip off!
Anonymous is correct.
=) Happy to help.