Do I need to do a clean install of Windows 10?

Episode 1512 (1:26:38)

Mark from Lake Havasu, AZ
Windows 10 Start Menu

Mark is upgrading his Windows 7 laptop to Windows 10. Can he just upgrade or should he do a clean install? Leo says that he still prefers a clean install, but the truth is that the recent Windows 10 update makes clean installs unnecessary. He should still back up, though, just in case. But then he can go ahead and upgrade it. If there's problems, then he can resort to the clean install.