Windows Phone; Windows 7, 8, 9; Windows RT; Windows CE; and not to mention all the different variations of Windows boxed OSes (Pro, Basic, Home, and so on): there have been a lot of different products that bear the name Windows, and someone has probably decided it's time to simplify.
The idea would be that, in the mind of the consumer, Windows is just Windows, and that all of these different names and flavors are just confusing ("Why is it called Windows Phone if it can't run my Windows programs?"). Getting rid of all that complexity and returning to the old way - where Windows is synonymous with personal computing - would certainly be a coup for Microsoft. But just as it shot itself in the foot with Windows RT, consolidating on just "Windows" could be fiscal suicide if Microsoft's various operating systems don't indeed come together as one harmonious platform.
The folks at ExtremeTech have noticed a shift in nomenclature and marketing focus these days, as several products have simply discussed
Windows, with no emphasis on anything other than that single word. The challenge here is that what marketing wants can't be delivered by the technical teams behind all those different versions of Windows operating systems, as they are not just different codebases, but extremely different code bases.
Nadella was handed a royal bag of shit, you have to admit. Consolidating the mess is a worthy endeavor but only if he can truly consolidate it from an engineering/code perspective instead of just relying on snappy marketing. Ballmer should be punished to wear a "Plays for Sure" t-shirt at every basketball game he attends, as punishment for the debacle that was seen in that marketing ploy. The t-shirt should be colored poop brown, like a Zune - another debacle. And on the back should be the words "I squirt," like the verb his team came up with for transferring pictures or music from one zune to another.
Good luck, Nadella. Remember, if you light the bag of poop on fire, you'll have to drop it when it burns your hands and then squish it out with your shoe to put out the flames.