It also depends on native language. In German ground floor is "Erdgeschoß" (earth floor more or less), first floor / American second floor is "1. Obergeschoß" (~first upper floor).

(can also be "1. Stock" (~first floor), very common especially in spoken language since it's shorter, but it also wouldnt make sense if the "1. Obergeschoß" was the "2. Stock" so obviously "1. Obergeschoß" = "1. Stock")

So for me the British system makes much more sense since it makes more sense in German and I grew up with German.

In Sweden and Netherlands we do ground floor, 1, 2, 3 as well.

yes without bias I know they have 32 degrees freezing temp and something like 243.7 as boiling temp, and 12 inchs as 1 foot, and 1 lbs is like 2.2 of water required for heating up 1.018 energy and all are messed up, but at least they call the first floor first floor, and second floor second fucking floor upstairs. for some reason ground floor implies basement to me