Linux may well be one of the most stable and reliable operating systems out there, but you should still plan for failure. Linux still depends on PC hardware and a steady power supply to be able to function properly. If you are administering Linux servers then this would be a no brainer, but even desktop users should bear it in mind. After messing up my first couple of installs it was something I quickly learned once I was up and running again. There’s nothing more frustrating than spending a couple of hours getting things just the way you like them to lose it all when you mess up!