I have a 1 TB WD Black HDD that I used strictly for media storage. I often find myself going 2-4 weeks without doing any writing to the drive at all. So that makes me wonder, is it good for it to just sit there running the entire time or should I disconnect it (SATA) when I anticipate that I won't be using it for a while? I figure with it unhooked, that is far less power cycles that it will see over its lifetime, I would essentially be treating it as a external HDD held in the case
If you really don't use it that often and if it's not really annoying to have to start it up whenever you want to use it then I'd power it down between uses. The benefit isn't just reduced wear and power consumption, it also isolates the drive against things like viruses, accidental deletions, etc. for the period of time that it's disconnected.