I think you misunderstand how the European numbering works. Think of it like Europeans count the separations between levels. There is no 0th separation, the first separation is the ceiling above the ground level. Saying that the ground level is the "first element" is begging the question - this is just not what Europeans count. (Well some do, but then they count similar to Americans, there is still no 0th floor ether way).

It is true that some elevators label the ground level 0, but this is usually when there are also negative levels (cellars).