It was only when the design was able to pass strict enterprise-grade Zero Error standard of 400 units surviving 500 hours of the toughest continuous testing without a single error or failure that the drive was manufactured.

ENGADGET: Plextor M5 Pro bulges SSD envelope with 94K IOPS and 540MB/s

Even worse, when the testers find an error, and they mostly will, we have to do the whole cycle again: bug fixing and re-testing.

FORBES: Machiel van der Bijl On Automated Software Testing