Over the years, Microsoft's made some incredibly good moves, even if they felt like mistakes at the time: mashing Word and Excel into Office; offering Sabeer Bhatia and cohorts $400 million for a year-old startup; blending Windows 98 and NT to form Windows 2000; sticking a weird Israeli motion sensor on a game box; buying Skype for an unconscionable amount of money. (The jury's still out on the last one.)

Along the way, Microsoft has had more than its fair share of bad mistakes; 2012 alone was among the most tumultuous years in Microsoft history I can recall. This year you can bet that Redmond will do everything in its power to prove 2012 naysayers wrong. To do so, Microsoft must learn from the following dirty baker's dozen of its most dreck-laden decisions, the ones that have had the very worst consequences, from a customer's point of view.