Plumbing

This weekend I've moved a water faucet 2 meters and stopped another one (as part of a minor wash room project). I'd prepared meticuously and gotten all the spare parts needed. But I know how it is - so I started early saturday morning knowing that I would probably need to go to the shop to buy something extra. After dismantling most of the old stuff I needed to put in a 90 degree angle thingie. And sure enough - the one I bought didn't fit. I had bought a ½" and the one sitting there was made for a 18 mm pipe. Down to the shop I went - and it turns out there was no direct subsitute with what I bought. I ended up having to do all kinds of ugly go-betweens to make it fit. Now someone tell me why we don't use a standardized size of piping - I don't get it. And it sure ain't userfriendly!