meaning - format the hard drive to remove any and all previous versions of Windows. There's no debate about it, it's the best way to install any OS. And that's straight from MS, where I was employed for many years.
I couldn't agree more with the clean install advice. It's too bad if you really don't have that option. Laptops typically come bloated with tons of crap you don't need. I prefer to do a clean install on them when they are brand new, even if I'm keeping the same OS.