On Tue, 26 Apr 2016 08:50:11 -0400, Wolf K wrote:

But that's because it's a _decimal_ system, _not_ because the
quantities themselves are useful. In fact, in real life they're
damn inconvenient, because they don't relate well to sizes and
quantities we humans actually use.

Probably that's why the system is based on metres, kg and seconds,
which we can all relate to on a human scale.