What are the risks if I never connect a robot vacuum to wifi?

Pretty much what the title says. I’m interested in getting a robot vacuum, preferably one that self-empties, but of course the self-emptying ones also have wifi connectivity, mapping, etc. My question is: if I never connect to the wifi, is there still any risk of hacking, privacy violations, etc.? If so, is there a way to mitigate that risk?

One other question: if I buy a used vacuum that was previously connected to someone else’s wifi, reset it to factory …

connect connectivity course etc hacking mapping privacy question risk risks robot vacuum wifi