Backblaze, a cloud storage company, recently posted their 2015 hard drive statistics and reliability report (click here), which may be interesting reading for some.
Keep in mind this is a report based on their own internal findings and use of disk drives in their datacenter, and is not a broad survey of hard drive reliability from various users and organizations.
So, for example, if you read through the report, you will see that they have nearly 30,000 various Seagate hard drives in use, versus over 12,000 HGST drives, but only 46 Western Digital drives.
This is not to knock their report … in fact, I found it quite enlightening.
Enjoy!