Perhaps a silly question, but I'm simply not sure of the answer.
The background: My main desktop harddrive started showing some pre-fail behavior during the "fast" SMART tests, and wouldn't complete the "long" SMART tests. Occasionally (usually after a day or so of use), the root (ext4) partition or my user's home partition (also ext4) would remount as 'ro', which forced me to reboot, fsck, and so on, but invariably it'd happen again. A fsck when the drive was "fixed" reported no errors, but they'd quickly crop up again.
So I cloned the entire hard drive to another of the same model, using gparted (from the Siduction live DVD) and stuck the new one in. No problems... for about a day. Then it started having the same problems (including failing the extended SMART tests), and bad sectors upon fsck'ing.
My (perhaps stupid) question is this: The new hard drive was supposed to be new, and shouldn't really be in a pre-fail state, unless it was part of a bad batch. The fact that the extended SMART test keeps failing at apparently the same point sort of indicates the same sort of error in the drive. But the SMART stuff is ONLY for sector/hardware based issues, right? It shouldn't have been affected by cloning the old, failing drive, so far as I know.
Am I just unlucky with these drives, or could there be something more nefarious going on?