I had to do something like this. Not every hour, but several times a day was needed to keep this person on track and productive. And no, I did not want to check on an otherwise-functional adult that frequently. Nor did anyone else, but circumstances led to them working on my team.

> I think in such cases it might be better to get rid of such staff, for your own sake and theirs.

Yes, that was the best option and is ultimately what happened. Going through the required HR hoops was just as much effort as micromanaging, which is why no one bothered to do it for several years. It was easier to shuffle them off to another project and tell the lead "they're alright, they just need to work on communication".