It's not impossible to have a drive appear unreliable in one machine and reliable in another (if you physically move it). There could be something electrically or mechanically wrong with the machine which causes a particular drive to malfunction more frequently.

If you see this repeatedly with one machine, I would definitely consider that it is the machine which is bad rather than the drives. A power supply may be insufficient to support the peak requirements of the drives, for example. A poor mounting structure might resonate or transfer vibration or shock into one or more drive slots from the environment.

Vibrations can be problematic in multi drive chassis. The more NAS rated drives are apparently rated specifically to deal better with vibrations and of course the NAS itself some isolate drives far better than others from each other.

It might seem minor, but just watch this rather old now but infamous video of Brendan Gregg shouting at HDDs causing significant drops in throughput: https://www.youtube.com/watch?v=tDacjrSCeq4

fun video! it doesn't take much vibration. (or he's just an incredibly loud screamer.)

thanks for that interesting note. i had been thinking only about heat as a cause of trouble in that enclosure (an old Netgear ReadyNas).

As others have mentioned, vibration can be a problem in these environments. But heat is also something you want to deal with. Clean power is also something to be concerned with.

In the past I've used a lot of those Supermicro 5x3" drive carriers and they have really good airflow. This was for storage in servers I built for home use. I wrote up something in 2008 about one I built here: www.tummy.com/articles/ultimatestorage2008/

Faster spinning disks generate more heat and vibrations than slower spinning ones. 15K drives are notorious for needing good environmentals.

My current storage needs are pretty limited, which probably would make SSD attractive. Or we are getting there at least. My storage server right now has 6TB used, and around 1TB of that is backups. If I could get by with 4x 2TB SSDs, I might consider it, just for longevity sake. I'm using ZFS BTW.

I built up a homebrew NAS with three of those Supermicro drive bays, and, other than the need to remove/replace screws (and not lose them for empty bays), I've really liked them.

However, I can't for the life of me find out whether or not those bays will work with 6 Gb/s SATA. I've been considering putting my Ryzen 7 board into the NAS case to consolidate two systems into one, but I'm not going to go to that effort if I have to get new hotswap bays.

Yes. I used to see equipment -- hard drives, video cards, motherboards -- burn out at least once a year, and then I installed a power conditioner on my hardware. That was 4 years ago. Last year, for the first time in 17 years, I upgraded my motherboard by choice rather than replacing it after a failure.

AFAIK Google have said they never really find any correlation between SMART errors and actual drive failures.

Interesting. Have not heard that before. My anecdotal experience in that NAS enclosure with Seagate drives was that when, IIRC, "Reallocated Sector Count" started to go up week after week, the drive would fail within a few months.