WD Hard drives for long time storage

I have many WD external hard drives, easystore, my book, passports. Some I have had for 5-10 years and they work great! Using them as storage devices, is it better to leave them plugged in (powered) than unplugged for long storage (unpowered). Does it matter?

I’ve had hard drives fail whether they been stored away for few years or used for years.

I would highly recommend whatever you have … have a backup hard drive

eg. I’ve got a lot of important data stored on a 4TB Hard drive … which is all backed up onto another 4TB Hard drive. (whenever i buy hard drives, i usually buy 2 of them)