Check this report from backup service Backblaze out. They outed a report of their hard drive failure rates, it was done with a very respectable 25,000 hard disk drives. The chart shows a failure rate for all tested HDDs, and check out the SeaGate 3TB .. topping a failure rate of 40%

the Barracuda 7200.14 3TB is failing at incredible rates over at Backblaze's datacenter. This doesn't mean all Seagate HDDs are bad though, the newer Desktop HDD.15 4TB had a failure rate of only 2.5 percent across a sample of 12,000 units. The vast majority of the 3TB Seagate failures are tied to a single model: the Barracuda 7200.14. That drive's annual failure rate jumped from under 10% at the end of 2013 to over 40% a year later. There's no indication of why those 'cudas are failing at a dramatically higher rate, but the sample size is pretty big. Backblaze has over 1,100 examples with an average age of 2.2 years.

Although the 3TB contenders from HGST and WD also suffered higher failure rates over the past year, the overall percentages are much lower—especially for HGST. Drives from that manufacturer, which is owned by Western Digital, continue to be the most reliable in Backblaze's storage pods.

Updated reliability stats on 17 different drives are available in the full report, which is worth reading. Updated with Q3 2015 results:

Seagate 3TB HDDs has huge Failure rates