@hazlin @skylar >The Meter is based off of an error
The metre is not based off an error.

They decided to arbitrarily use the polar circumference of the Earth as a measurements, with mathematical calculations, but ever so slightly got one of the measurements wrong, but that didn't matter in the end, as the distance could be perfectly replicated and the polar circumference of the earth happening to not actually be 40000km doesn't matter.

The inch is based off the metre, being defined to be 25.4mm.

>They may have well made it the same length as a yard.
There was no replicatable measurement of a yard and the error rate of basing it off as something as short as a yard rather than a whole planet would be rifle with terrible inaccuracy.

The yard is now defined based off the metre, being exactly 0.9144m.

>An extension of existing units
The existing units *could not be replicated*, thus they were useless for any sort of accurate measurement purposes.

>introduced a competing system, with slightly different unit sizes for no reason
The unit sizes were all unique and carefully selected for a reason.

>The baked in usefulness of the traditional units lost.
Such units had no baked in usefulness - they were inaccurate from the very start.

>A system based off of foolish pride and ignorance, that created more work, for no benefit.
A system of using metric with extra steps that is based off foolish pride and ignorance, that makes more work and causes errors for no benefit is what the US customary units system is.