do all roman clocks always write number four as IIII instead of IV

No, not all Roman clocks write the number four as "IIII" instead of "IV." While it was a common practice in some historical Roman clocks and sundials to use "IIII" for the number four, this is not a universal rule. Modern Roman numeral clocks and watches often use "IV" for four, adhering to the standard rules of Roman numerals.

The use of "IIII" for four in some older clocks can be seen as a historical tradition or stylistic choice rather than a strict rule. It's important to remember that practices may vary depending on the time period, region, or specific clockmaker.

In summary:

1. Some older Roman clocks and sundials use "IIII" for the number four.
2. Modern Roman numeral clocks and watches typically use "IV" for four.
3. The use of "IIII" or "IV" can depend on the specific clock or historical context.

It's always a good idea to check the specific clock or source when interpreting Roman numerals. But in general, "IV" is the more commonly accepted representation of the number four.