Another interpretation is that OS are a commodity. The days when the market eagerly awaited the new Windows and queued outside stores at midnight, are gone.

If you look at the devices the bright young things are using, prevalent devices mostly are not Windows and they don't know or care what OS their device runs, as long as the brand is cool. Increasingly the MS brand is not cool. It's a grandpa brand, like Buick.

MS also paid heed when even business resisted upgrading from WinXP. For business, new OS no longer brings much business advantage. The risk of continuing to release Windows versions into this market is that you throw a party and nobody comes. Especially when Google has a party across town with free entry. So for MS the way forward is to charge for services, or subscriptions to get stuff. They need to transform as did IBM after MS ate its lunch last time this sort of market shift occurred.