It is too precise for an absolute global position. But for relative posistions, i.e. the difference between to positions, 1 cm is about right. It is close to t

It is too precise for an absolute global position. But for relative posistions, i.e. the difference between to positions, 1 cm is about right. It is close to the resolution in the best aerial images. So if you you want to map e.g., a park bench as a 2-dimensional object og the layout of railway tracks you need the precision. When you zoom in a lot on a digital map you still want the details even if it is all off by several meters. Just as you can have detailed printed maps of a small area.