[nske]

It might be what you say, but in many cases it might also be a necessity. I built my first array with 10x1TB disks (starting with 3) for my home server when I was a student/got my first job and could only afford one disk every now and then. Linux' expandable mdraid worked like a charm multiple times. I probably wouldn't have bothered (and would have lost data or limited my hoarding) if I had to save for a year just for a fileserver. I am not talking about precious data but data don't have to be irreplaceable to want to protect them.