When I can make a coffee, till clean installed Windows 10 opens an explorer, that is really ridiculous.
Well that would be a problem somewhere. I've had good luck with hardware for the most part, but sometimes if a driver isn't getting along with Windows it can really throw a spanner in the works. Another thing that can get you is too much stuff loading at boot. Mostly what gets me are bad tweaks where I have to back up and figure out what I did wrong. Been a Windows user since the beginning so I've seen all its warts come and go.
It's possible to store user files in a folder other than the videos, documents, music, etc folder which are created during windows installation. So IMO there is nothing to worry about it. But others may have different views.