Show of hands: Just how many people here back up their ones and zeros and how many people have had to actually use that backup to save their butts because of some hardware or software meltdown? Using a backup because you mistakenly deleted something or another doesn't count as an instance of the latter.
Further, for how many people here would life end if they did loose a hard drive or two? Not how much of a pain in the butt it would be, but actually stopping breathing.
If you fall into that latter class, you don't need backup, you need therapy. You need to find a way to conduct your business without complete dependence on technology. If you cry out that it can't be done, look around at those who would respond that their lives would go on. What do they know that you don't?
Do I backup my stuff? No. I admit to keeping a CDR/W with my font directory on it but that's just as much to keep multiple machines in sync as it is self preservation. But for the rest of it, there's not much I can't rebuild in a matter of minutes. I don't fret all that much about losing previous work. It was, after all, previous and I've already been paid for it.
Moreover I know that the probability of any backup being bad is exactly the same as the primary data being bad. Backup is just something else that can go wrong. If backup is simple, easy, requires no time, and costs nothing, why not? If it isn't any of those things, why?
Before your collective knees dislocate themselves from jerking, consider that I've been dealing with computers, all facets of them from design, construction, repair, programming, and operation, for close to a half century. Not only do I have some ken of the matter, I also know full well that life is possible and just as pleasant without them as with them.