When people's names are listed with both sides aligned (either in horizontal or vertical writing), for example, in the ending scroll of a movie, there is a seemingly complicated rule (to me).
When the length of the name (family plus given) is not three characters, the positioning is such that the characters are distributed evenly, without particular segmentation between the family and the given name parts:
X* = family name, Y* = given name
X Y
X Y Y Y
X X Y Y
X X X Y
X Y Y Y Y
X X Y Y Y
X X X Y Y
X X X X Y
However, when the length is three, it seems as if a space character is inserted between the family and the given parts and the positioning is done counting in the space character, like this:
X Y Y
X X Y
Considering the rules for the other cases, I would rather expect:
X Y Y
X X Y
Why is it like as is? Is there a rule behind that makes the length-3 cases non-exceptional, or is there a reason why length-3 is exceptional, or, is it just due to inconsistency/stupidity of whomever started it?
Edit
Or to see it from the other side, it is natural that a space be inserted in between the family and the given names (as Dave points out in the comment). Then, why are the cases other than length-3 (except the length-2 case, which can be interpreted in either way) not having a space? I would rather expect:
X Y Y Y
X X Y Y
X X X Y
and so on.
Edit These are links to some pictures that describe the situation (with some variations):