I remember reading that IIII also made it easier to create the numbers in the first place. A watchmaker would mold VIIIIIX four times, the first would be cut as

I remember reading that IIII also made it easier to create the numbers in the first place. A watchmaker would mold VIIIIIX four times, the first would be cut as V, IIII, IX ; the second as VI, III, IX (the latter rotated to become XI) ; the third as VII, II, I, X ; the fourth as VIII, IIX (the latter rotated to become XII).