Comment by lproven

> They never heard of making a UI, and just slapped buttons.

I suspect that floor numbering predates lifts (elevators) by centuries.

Stairs are ancient.

I mean, zero itself is a non-obvious concept. Its invention is a matter of historical record:

https://www.open.ac.uk/blogs/MathEd/index.php/2022/08/25/the...

... and we still use counting systems which predate the invention of zero, such as Roman numerals.