Modern disks are very reliable. In our lab, we see most disks able to handle over a billion read and write requests without encountering any errors. This is the number of requests a typical disk gets in 3–5 years of use in a workstation or server.
If you see a disk with an error, even just one, something is wrong. It might be something as simple as a bad cable—or it might be something much more serious like a failing power supply, or a failing disk.
