

But, if you like an idea of giving your Mac a fresh start with a new macOS and nothing else, a clean install is the right option for you.

It saves all your personal files, apps and user data, while a so-called clean install of Sierra will erase all data on the startup drive and replace it with a clean copy of OS. What happens when you install macOS Sierra? A clean install will delete everything associated with your profile, all your files, and documents, while the reinstall will not. Please note that if you need to remove the data and reset your Mac to factory settings, go for clean install macOS High Sierra. Does installing Mac OS Sierra delete everything? The upgrade process is smooth, the changes are minimal enough that they won’t affect anyone’s workflow, and in general, the new features all good for everyone. If your Mac is less than a few years old and you’re pretty invested in Apple’s ecosystem, then it’s a no-brainer to upgrade to Sierra right now.
