Why do some international football teams have the players name on their back and others don't?

Answer 1

Players don't always have fixed squad numbers in international teams like in club teams, so it isn't always practical to put the names on the backs of shirts. Another reason is that sometimes a player may have to change a shirt during a match if it got ripped or covered in blood, so it would make no sense to have to put on a shirt with another player's name on it. For these and other reasons it is often simpler not to have the names on the shirts.