I Have a Thought! More Like A Question!

[Been There]

I'm pretty dissatisfied with Windows 10 Home on one of my three computers. So, I came up with the idea... Remove the Hard Drive that contains the W10 OS, and install a fresh "New" Hard drive and take my Windows 7 Home disc and install it on the new Hard Drive. This way I can have Windows 7 , and if I can go crazy and think I will ever love Windows 10, just remove the Windows 7 hard drive and install the Windows 10 hard drive and not have to pay Bill Gates his fee.

 

[Trouble]

I suppose that, that constitutes a "plan" of sorts.
Although you would likely miss out on interim Windows cumulative updates while on Windows 7, which may (or may not) address some of the issues responsible for your dissatisfaction currently with Windows 10.
AND
The computer that currently has Windows 10 installed (and activated) will or at least should always qualify for a re-install of Windows 10 should the mood ever strike you and assuming no drastic hardware changes and that you have the installation media on hand.

Personally, IF I were going to invest in another hard drive I would probably use it to maintain current disk images of my install(s), which would allow me to switch to what I wanted, when I wanted.

 

[Been There]

Wouldn't it be a idle (disconnected) Win10 hard drive without any connections to the motherboard, etc.? And the Windows 10 updates...if any would be available when re-connected to the computer. Same would be if I set the computer aside with the power cord removed and year or so later re-powered it up, the updates would download and install. I would guess that would work.

 

[Trouble]

Yep..... that's all... you'd just have to play catch-up is all.
AND, with Windows 10 on and soon 7 & 8 going to the cumulative update model it probably wouldn't be as loathsome as previously.

 

[Tim Locke]

I would leave the machine plugged in. Otherwise you might find the onboard battery is flat when you use it again.