Earlier quoted context omitted.
Apple bundles the OS with the hardware. Once you buy a Mac, you get free OSX updates until they no longer support your model for the new OSX versions. The cost of OSX is bundled in the price of the Mac, which is why Macs cost more than PCs. Microsoft cannot do that because OEMs sell PCs and bundle Windows with it. A totally different business model than Apple has. Steve Ballmer tried to copy the Apple Business Model…
I don't see it as totally different. The vast majority of Windows users get their license with their PC purchase. That's where Microsoft makes the bulk of their money. I suspect most users never upgrade from that version unless they buy a new PC. So giving free upgrades is not a big loss for Microsoft; it was never a big income generator.
I bought Windows 8 Pro upgrade for $40 when it came out.
Microsoft might give Windows 10 out for free to make money on the Windows Store that sells apps, movies, music, and other things.