It builds a millimeter-accurate map of your home, and in some cases, that map leaves your house.
Most people have no idea any of this is happening, which is exactly the kind of thing that should probably bother us more than it does.
Here's the pitch you get at Best Buy: LiDAR, vSLAM, multi-floor memory, no-go zones.
What you're actually buying is a roaming sensor platform that learns the exact square footage of your kitchen, where your bedroom door sits, and roughly when you're not home.
The mapping itself is genuinely impressive.
Modern units spin a laser turret thousands of times a minute, bounce light off your couch legs, and stitch together a floor plan you can edit on your phone.
It's how they avoid your dog's water bowl and stop eating charging cables.
None of that works without a map, so the mapping isn't going anywhere.
Some brands process everything on-device and only store the layout locally.
Others push it to the cloud so you can start a cleaning run from the office or yell at Alexa to hit the hallway.
Cloud features are also someone else's hard drive.
Remember the 2022 reporting that a Roomba's captured images of a woman on a toilet ended up in a training dataset viewed by gig workers?
The company said it was a test unit and the images never should have been shared.
That's the exact vibe you want from a device that memorizes your floor plan.
Then there's the quieter problem: the map is basically a home inventory.
A floor plan with furniture positions tells a burglar or an insurer or an ad network more about your life than any loyalty card ever could.
Whether your smart vacuum is quietly phoning home is a question worth asking before you name it and give it a personality.
First, read the app permissions and find the toggle for cloud versus local storage.
It's usually buried three menus deep, because of course it is.
Second, if you don't need remote start, consider turning off cloud sync entirely.
Third, set up no-go zones over the bathroom and anywhere else you'd rather not have photographed.
None of this means you should toss the vacuum.
It's still the best $300 you'll spend to never touch a broom again.
But "it cleans my floors" and "it knows my floor plan" are two different products, and you're only paying for one of them.
The honest take: robot vacuums are great, and most people will never notice the mapping tradeoff until something leaks.
Check your settings once, turn off what you don't use, and enjoy the robot.
Final Thoughts
Just don't pretend it's only a mop with wheels.