The arabic numeral system is base-10, but English numerals are only sort of base 10: consider 2, 10, 12 and 22. In English, these are spoken as "two", "ten", "twelve" and "twenty-two". The words "twelve" and "twenty" are both derived from "two", it's true, but in two different ways. "Teen" and "ten" are similar, but there's nothing about "twenty" that indicates a connection to "ten".
In Japanese (IIRC), 2, 10, 12, 22 is spoken "ni, ju, ju-ni, ni-ju-ni": "two, ten, two-tens, two-tens-and-two".
It's not that one base is better than another: the idea is that a single consistent base is better than inconsistency.
Thank you. I had flirted with the thoughts before, but never really explicitly considered how odd the English words "eleven", "twelve" and then the "teens" are. Not only is "teen" not quite "ten", we also put it after the ones digit. That is, 19 is "nine-teen", but 91 is "ninety-one".
This is true of Germanic languages more generally, where they have special cases for teens too but also read higher numbers as "five-and-twenty" etc. And then French has their vigesimal thing - 92 is quatre-vingt-douze, ie. "four twentys and twelve". English gets off relatively lightly with teens only...
Interestingly, this is how I was always taught to think of numbers. Beads on a stick represent all numbers. 1 bead is 1. A ten is therefore a stick with 10 beads on it. A hundred is 10 tens (in a square). A thousand is 10 hundreds stacked on top of each other (or 10 "10 tens" in a cube).
This really made it simple to think of things like carrying (oh, that's just breaking the wire holding the beads together) and squaring/rooting (since 100 was a square of 10 it was trivial). It provided an interesting method of multiplication too (simply align two numbers orthogonally and fill in the grid). I still think in terms of this now.
Incidentally, when I learned Japanese many years later it felt more natural than saying twenty-two or the abomination that is seventeen.
20 is "esrim", meaning tens, which is actually a special case because Hebrew once had a grammatical dual form. Then comes "shloshim", meaning threes. "Arba'im", fours. And so on. So 22 is "esrim ve'shtayyim", tens and two.
In Japanese (IIRC), 2, 10, 12, 22 is spoken "ni, ju, ju-ni, ni-ju-ni": "two, ten, two-tens, two-tens-and-two".
It's not that one base is better than another: the idea is that a single consistent base is better than inconsistency.