Can I trust a robot vacuum on a shag rug?

Probably not. Thick shag rugs are basically a trap for most robot vacuums—the long fibers tangle around the brush roll, and cliff sensors mistake the deep pile for a drop-off, causing the robot to stop or get stuck. Some high-end models with self-cleaning brush rolls or advanced sensors might handle it, but it’s still a gamble. Save yourself the frustration and stick with a manual vacuum for that room.