It’s because volume is 3 dimensions. Length, width and height. When it’s only length, the factor is 100 (10x10) and width this assumed to be 1.
When you add the other dimension, in this case height, the factor is 1000 (10x10x10).
In the Pharmaceutical business, all we use is metric because it is Globally universal and far more precise than the English system. It is also far easier to do calculations with.
