What are mapmakers referring to when they talk about balance?

When mapmakers talk about balance it is about element placing. They need to make a map that is not crowded but also not full of blank space or any blank space at all. This leads to them excluding many elements of a given region just because there is not enough space on the paper to put it on. In order to put more elements on a map, map creators create maps of different scales and regions so that more details could be incorporated into a map.

Distributing the elements of a map evenly, without crowding or blank spaces.