My take is that there is more value in moving you into their Windows operating “environment” for future sales and service, not the hardware value. They pay less for MS products because you are already in the family.
Remember -- Windows 10 is "Windows As A Service". Don't you ever fail to apply all the Windows Updates.
Microsoft's Tyer Myerson said that "once a Windows device is upgraded to Windows 10, we will continue to keep it current for the supported lifetime of the device at no charge."You didn't apply all of your Windows Updates? You lose -- your Windows starts costing you money at that point.What does that mean, really? Users must keep their devices supported. "Supported" means apply ALL the updates. ALL of them.
"Updates are cumulative, with each update built upon all of the updates that preceded it. A device needs to install the latest update to remain supported," Microsoft states in fine print.