Biggest Micro$oft screw-up IMHO was their Windows phone. That would have added a lot of WP10 devices and cross-platform commonality. But, they decided to focus on HW instead of SW and carrier support, which has never been their thing, and only ended up destroying Nokia and its future in the process.
Now the only choices in smartphone land are devices from the even more uber-lib-run Apple and Google empires of anti-freedom and love for big government.
We agree on that -- the "failure" is merely the failure to accomplish a highly-hyped and very visible/public goal. But that matters tremendously to sales people and the markets that hang on Microsoft's coattails.
> W10 is the best Windows yet in my opinion.
Glad you like it. I find it usable, but prefer 7 personally. Ain't it wonderful to have a choice? :-)