[creatonez]

True, but the flexibility that two attempts at porting to botched architecture introduced also resulted in 2003 becoming Microsoft's first x86-64 operating system. The very next day after the 2003 release, they released Windows XP Professional x64 Edition based on the 2003 codebase, which a user could run on their brand new x64 computer without much of an issue -- that is, if they had even heard of it... it was under-marketed because they needed to save the hype for Vista. So the struggle and failure may have been worth it in the grand scheme of things.