Extending life expectancy of USB external hard drive

I have long used two desktops; one at home, one at work. For working storage, external HDD was my choice since I didn't like having my data saved on a commercial cloud service for which I have little control. (A definitely outdated and inefficient way; I now use cloud at least partially). So far I used three different external HDDs. 1TB from Seagate / Toshiba / Western Digital. The first two gradually died in about a year, but the last and the current one survived over 3 years and 4 months. In fact this baby showed some death sign recently, so I bought another one, but I didn't have to open the package.

The biggest difference is that I paid a lot of attention with the current one when disconnecting it from desktop. In the past I force unplugged USB cable even at the error message saying 'Windows can't stop your device upon ejection attempt, assuming it be okay since the read / write process should be completed. Now I have it a rule to set the HDD offline first upon ejection failure, although I still force unplugged infrequently. Probably less than 1%.

One needs to go to Control Panel -> Administrative Tools -> Computer Management -> Disk Management, right click and HDD, and then check 'offline'.

Note that, if you disconnect the HDD after setting it offline and reconnect, then the autoplay doesn't pop up, and the HDD won't be visible in the Windows Explorer. You have to manually set it back to online using the same context menu as the above. This could be a problem in particular when you come to work the next day, but do not remember that you manually have set the HDD offline. So I typically reconnect the HDD and restore to online right away.

I do not clearly remember the symptoms of dying HDD since I haven't had the issue for the last ~3 years, but I think being unable to eject your HDD normally progressively more often was one of them. By then, you might start seeing warning like 'this device can perform faster if you connect to USB 3.0 port blah blah..' even though it is connected to USB 3.0 port. Or FAT system of the HDD becomes corrupt so that you cannot read some files. In the end your entire HDD becomes inaccessible. Or you will see a message like 'this drive is not formatted. will you want to format?'.

In short, I strongly recommend you to safely disconnect your HDD; meaning that you should make sure that the HDD is truly ready to be disconnected, sometimes by manually setting if offline.