A certain nano-laboratory is developing new products of "nano" accuracy. For example, if they develop telescopes, they do not permit an error of even a nanometer in the lenses, because this will result in great error when put to use.

The first project of this laboratory is producing nano-purified water - that is, no ion is allowed to have a concentration of more than 1 nanomole per liter.

No matter how hard they tried, their endeavours always resulted in failure.

Why?