The strange thing is the symmetry. Why these prefixes cover multipliers from 10^-30 to 10^30? Why not 10^-20 to 10^40? Where the symmetry comes from? Is it jus

The strange thing is the symmetry. Why these prefixes cover multipliers from 10^-30 to 10^30? Why not 10^-20 to 10^40? Where the symmetry comes from? Is it just people think that symmetry is a good thing, and for example they added 10^-30 despite the lack of demand? Or there is some deeper reason? Or it is more like one of those coincidences?