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http://www.techspot.com/news/52047-what-is-false-disk-failure-and-why-is-it-a-problem.html

• 2/100 drives fail per year (it's actually much higher for the drives ChemIT uses!!)
  You can expect something like 1/100 of your drives to really fail this year. And you can expect another 1/100 of your drives to fail this year, but not actually be failed. You'll still pay all the operational overhead of not actually having a failed drive – rebuilds, disk replacements, management interventions, scheduled downtime/maintenance time, and the OEM replacement price for that drive – what $600 or so?

Can we reduce the consequence of hard drives failing, and at what cost/ benefit?

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