Having spent far too many hours working with Unicode, I think this story of UCS-2 and how it failing to become the standard caused all sorts of trouble, is interesting.
Around 1996, the Unicode consortium decided that no, 16 bits was not enough. They had decided that Unicode should not encode all modern scripts in use today, but instead every script to have ever been created by humans. […] However, all these products had already codified 16-bit code units. They couldn’t simply unship their products, go back to 8-bit code units, and migrate to Plan9’s UTF-8. (Please note that UCS-2 was being pushed as “the only way to do Unicode” initially, and UTF-8 didn’t come out until January 1993)
Henning's blog 