Funny. I have a robot vacuum that I have to refill the water tank periodically and empty the dust bin. Even with your limited example, there's value in the automation. Thankfully they aren't restricted to just that. It's their first robot after all.
You want a robot that does the task well enough AND for which if it fails it's not a big deal if it's not too often.
For bigger robots that can break stuff it will be too annoying, but for Maurice, I don't think so.