There's a lot of speculation here, but no need for much of it: the drive firmware records exactly what the issues are, and reports it via the S.M.A.R.T. interface.

Under Linux, one can read all of the data, along with the firmware's specified pain/temperature thresholds, with this command:

smartctl -a /dev/sd?

If a drive got too hot, it will show it.
If a drive developed media errors, it will (normally) show it. Except WD drives are known to cheat here.

If the failures are due to bad cabling or loose SATA connectors, it will show it. That happened to our server here just last week: smart data indicated UDMA_CRC errors, so I opened up the box, and could see exposed gold fingers on the connector. I shoved the connector back into place and made a mental note to get out the hot-melt glue gun later on (perhaps today!).

Cheers