Dying mybooks

In the past 6 months I have had 3 , two teribyte “my book” drives die. The last one was sent to me to replace a dead unit by WD one week ago. Someone , on another. Forum, said that this device was not designed to be on all the time. I do not use this as a backup device, it stores the gigabytes of video that I work with every day. Is this designed to be turned on, used and then quickly turned off before it dies??? The power adapter, although small, is able to light up a 12 volt car tail lamp, so I guess the problem is not the power supply. Can anyone confirm that this drive is not designed to always be on?? Thanks

I will let WD tell you on this link :

Leaving an external hard drive powered on all the time