Well it isn't especially complicated, but there's a lot of neat ways you can integrate personal bots with third party APIs that wouldn't be allowed on the bot store.
For example, I have my personal (addmittedly mediocre GP/h) money making bot hooked up with an api to send me notifications/exceptions caught/updates through discord. And I can send commands back through discord as well to control it.
It's basically just more convenient TeamViewer.
I've never found a good reason to do so yet, but if you were to start gold farming hardcore you could use remote connection Interfaces like this or other APIs like JOOQ for a SQL db or something.
Lots of neat possibilities when you pull in third party APIs.
Edit: also I realise this isn't at all the type of complicated bot you were referring to but, ya know, just something out of the box