“We want all these Windows 7 users to have the sentiment that yesterday they were driving a first-generation Prius, and now with Windows 10 it’s like a Tesla.”
It looks to me that they now understand how bad the “Windows 8.1” name was. Plus it’s a marketing trick to upgrade sooner.. Bad call Microsoft!
Just imagine every product to start jumping version names! iOS 10 after iOS 8, Android 6 after Android 4, what else?