Well I have had a lot of hardware failures but not quite 6 within a year. I have lost a great deal of my maya work in two major disk crashes though.

One of which was several years ago where I learned a very painful lesson about striping drives. You may get a bit more performance but should you lose one disk out of the stripe then you lose ALL your data. Furthermore with each disk you add to the stripe the probability of single disk failure increases by n*(1/p).

The second was more recent and even more bizarre. I had all my new 3d works and major projects in an external storage appliance that was mirrored. One of the mirrored disks failed. I thought thank god I had the data mirrored. In the process of rebuilding the mirror the multiport controller of the storage appliance failed and corrupted the good half of the mirror and once again I lost ALL my work (nearly 2TB of data!).

So even when you think you are safe things can still go very badly. In those two crashes I lost at least ten years of work that I had accumulated. Some of which I was able to recover as I had it backed up in multiple places. But most was lost forever.

Therefore I agree with ND that off site storage and backing up to multiple external destinations are certainly good ideas if you can afford it.