Well, for one, I might have a big potential lawsuit coming up, and it spend about 7 minutes creating an extremely long years-long timeline based on all of the documentation on my computer, including timestamped communications, notes, emails, and tons of other legal documentation which I hadn’t thought to include. All wrapped up for the lawyers.
For two, I have a massive library of tools that I’ve written in one language or another for one given platform or another, and it’s really useful to port it over to another platform just by asking it to do so. It’s not so much plagiarism if it’s literally duplicating my own work onto the other platforms(which I test and verify, of course).
For three, it explains in much more specific verbose language that's good for me, instead of in simplistic language that tends to miss details. And again, yes, I verify the information it provides.
For four, I do genealogy research, and you wouldn’t believe how effective it can be in identifying people in others’ family trees who match individuals in your own family tree, allowing you to copy the details from those matching individuals and then copying in all kinds of family members you didn’t know about. I was doing it today, and I found my great-great-great grandma in Czechia, in a language I don’t speak, and her whole extended family including both parents(and marriage records and death records, et cetera), and more and more. I still haven’t seen how far back it goes for that branch, and that's just one. I’ve been using it to identify other branches in other countries as well. And that also led it to find photographs of many of the people who I’d never been able to see in person. And I was able to share with my family today people who it found from 100–200 years ago who looked a ton like living family members. I invited my mom over, and she literally started crying at seeing how cool it was.
There are numerous other useful aspects for "my own little plagiarism machine".