What is the importance of having a standard method of measurement such as (SI) ?

Question

What is the importance of having a standard method of measurement such as (SI) ?

Answer 1

A standard is needed so that people can agree on things. It's mostly political, but in a positive way. Without it, collaboration would be much more difficult.

The key thing is repeatability. The base units are chosen to be reproduceable anywhere in the world, and are continually being researched to improve their accuracy. As much as possible they are based on physical constants and not some arbitrary thing. (first link)

The exception is the standard for weight, which is a physical entity - the "standard" kilogram and its copies, which are literally just slugs of metal. A move is afoot to redefine the kilogram as a derived unit from other physical constants. (second link)

Answer 2

units are based on multiples of 10 so it's easier to make conversions from one unit to the next  

Answer 3

It enables everyone to have a common reference and so knowledge is more easily shared, collaboration is easier and there is a shared understanding.