Because what it means is you’re clearing the hard drive. You’re taking it back to the beginning, when the Universe was dark. All your files, all your programs, will be gone. Did you back up the files before you reset it to factory specs? No? Too bad. Do you still have the disks to reinstall the old programs? Who does?
Faced with the prospect of living forever slow or committing digital suicide, Bob took drastic measures: He uninstalled Google Chrome and Malwarebytes. Both of these seem to have become too demanding for old computers. So he switched to Firefox as his browser and everything is running fast again, as in the old days when the Earth was young. Joy tried Firefox too, and also found it clean and fast.
A couple weeks later we read that PC Magazine named Firefox as the best browser for the Internet.