[cptskippy]

I had a Roomba sometime after 2006 and it was dumb but not in a bad way. It had a drop sensor, bump sensor, and tire sensors. It would primarily move in a switch back overlapping pattern and had a couple different fallback patterns that would kick in if the bump sensor triggered to frequently. It didn't necessarily hit 100% of space in the first try but it could autodock and recharge, and had a couple invisible walls to cordon it off.

It got stuck occasionally and needed to be rescued but once you knew what it got stuck on you could clean up, as you would with normal vacuuming, and it would be mostly fine.

The newer robot vacuums have a lot more tech but don't seem to have improved upon the basic functionality much. They still get stuck a lot, have trouble with deep pile carpet, and don't get everything.