Ok I may be an idiot, but I just have a permanently attached external disk that does Time Machine, what am I missing out on? Why network location? Or are you backing up massive amounts of data? (for me it’s just 2TB)
It's mainly for multiple people in a household to back up to one location, especially if some have laptops that are often not on desks. Those Airport APs used to also let you attach disks for this. You could even do it over a VPN.
I switched to Borg on Linux server from local attached Time Machine disk after once I went to a long trip and forgot the disk at home.
Oh right — I could do a local HFS+ non-encrypted disk with encrypted Time Machine (I assume) — that just slipped my mind.