Nobody has realized that Satoshi Nakamoto never intended Bitcoin to group decimals by 3, but instead by 4, like in the japanese culture.

The radix point is exactly at the center:
0000 0000 . 0000 0000

21 million BTC = 2.1 peta-satoshi = 2.1 Psat
2100 0000 . 0000 0000

1 satoshi = 1 sat
0000 0000 . 0000 0001

1 finney = 1 oku satoshi (japanese group by 4) = 10 kilo-satoshi = 10 ksat
0000 0000 . 0001 0000