> Regardless of the size of the units, the first (or a single) item-unit is signified by the character 1, not the character 0. The character 0 is used to represent the absence of units.
I am afraid people are too irrational to stick with a totally uniform way of doing anything. The base of counting is no exception. Even in such a simple situation as counting years, we have (at least?) two systems: decades are definitely zero-based, e.g., we say "the 90's", meaning years [1990, 1999]; yet the count of years in the "current era" is one-based (the first year was 1 CE).
The difference was the ground for the popular debate whether the 21st century and the 3rd millennium started in 2000 or 2001.