Most cartoon characters have only 4 fingers (or 3 fingers and a thumb, to save Martin S correcting me 😃) because a four-fingered hand is easier to draw than a five-fingered hand. It also simplifies the design of the hand in the same way that the rest of the body is simplified. Hands with 5 fingers tend to look large and klunky.
Where the cartoons and animations depict people, the move is towards depicting the full set of 5 fingers on each hand, leaving the 4 fingers for the traditional cartoony depictions.
Interestingly, 4 finger depictions rarely appear in Japanese works. This is because:
- Yakuza members traditionally chop off fingers if they are unable to pay back a debt, or as punishment for other offences that don't warrant death.
- The four-fingered hand is taken as a derogatory reference to the burakumin social class (four fingers = four legs = animals).
- In Japan, four (四) can be read as "yon" (よん) or "shi" (し). The kanji for death is "shi" (死), which is why the number four is considered unlucky.
Whilst talking of fingers . . .