Google has published a report on the reliability of disks

Google engineers have published a report on the statistics of failures on a large number of hard drives. He again laid down the results of studying the work of 100,000 disks over a period of 5 years, which made it possible to find out many interesting facts.

One of the interesting fragments of the report:

Our analysis revealed some parameters of the SMART disk system that have a high degree of correlation with errors, but in spite of this we came to the conclusion that the prediction models based only on the SMART parameters cannot help in predicting the failure of individual disks. At the same time, it is surprising that the dependence on temperature and the active operation of a disk is noticeably less than previously reported.

Sources:
slashdot.org
Google Drive Reliability Report