[cs702]

AngryParsley: the Tom's Hardware article wazoox mentioned above also has those return-rate stats (page 3): "...returns can occur for a multitude of reasons. This presents a challenge because we don’t have any additional information on the returned drives—were they dead-on-arrival, did they stop working over time, or was there simply an incompatibility that prevented the customer from using the [device]? ... If online purchases account for the majority of hard drives sold, poor packaging and carrier mishandling can have a real effect on return rates. Furthermore, we also have no way of normalizing how customers used these drives. The large variance in hard drive return rates [between data sets] underlines this problem. For example, the Seagate Barracuda LP rises from 2.1% to 4.1%, while the Western Digital Caviar Green WD10EARS drops from 2.4% to 1.2%..."[1]

In short, the available return-rate data is too noisy and inconsistent to be a good proxy for failure rates.

[1] http://www.tomshardware.com/reviews/ssd-reliability-failure-...