Normal
AFAIK - once Win 10 is installed and 'activated' on a PC, it's licensed to that machine's hardware, so you can re-install it without needing the Win 8 media for licensing purposes. You can create a bootable memory stick with the Win 10 installer on it using the 'media creation' tool on the MS website, if you need to do a 'blank hard disk' install. Otherwise (as you said) there is a 'reset' option with Win 10 itself which basically does a re-install of the OS (but you loose all your installed software and settings). There are also some 'repair' options available.