Why many of us may have already bought our last car, according to the BBC

[Argent Stonecutter]

Should have stuck with Knuts, Sickles, and Galleons.

 

[Sid]

You're right about having to forget the old imperial units rather than doing conversion calculations, but that will come later, won't it? Surely other countries, even France in the Revolution, didn't suddenly wake upone day and know what 20 centimeters looked like.

After the French revolution, large parts of Europe where united for the first time since Charles the Great around 800. Europe had been a blanket made of hundreds of patches for about a thousand years, before Napoleon united them. Each one had been more or less independent, often with local currencies and measurements: Vadum, mutsje, duim, el, halfje, kan, pint, duim, voet, sleepje, anker, stoop, wichtje, vierde wichtje, taille, bos, lood, pond.
And these are only some of the measurements in use, in the patches that now a days form The Netherlands.
There was a real necessity to come to a standardization. The French really had to enforce those new norms with inspectors and fines. And it took a long time before whole continental Europe was over.
And even now a days in cooking recipes you can still find a cup, a tea spoon, a pound, an ounce and a pinch as measurement units in the descriptions.

In the US there is no necessity for standardization. There is one.
The British had to comply to the EU standards on entering the market. And read Tigger's post on how that went.