They forgot OS/2, which certainly was one of the worst tech marketing fiascos of all times and which helped plunge IBM into a dark place as Bill Gates laughed himself silly.

I still remember my shock when I (as a non-techie type) finally got it installed after hours of frustration only to find that few, if any, drivers worked on it - leaving you with all the theoretically great features in the world and at the same time unable even to print a document or do other basic things.