Wastholm.com

At the end of the 1990s, Korea developed its own encryption technology, SEED, with the aim of securing e-commerce. Users must supply a digital certificate, protected by a personal password, for any online transaction in order to prove their identity. For Web sites to be able to verify the certificates, the technology requires users to install a Microsoft ActiveX plug-in.

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It forced consumers to use Internet Explorer because it was the only browser ActiveX plug-ins were compatible with. By default, Web developers optimized not only banking and shopping Web sites for Internet Explorer, but all Web sites.

Unsurprisingly, this later caused all sorts of problems. And this, kids, is why "standardizing" on a vendor-specific solution, as opposed to an actual open standard, is an idiotic idea.