3 Reasons Not to Run a Robot Vacuum Without Cliff Sensors Near Stairs

It will fall off the edge Robot vacuums without cliff sensors cannot detect drops. They rely on bumpers and optical sensors for navigation, but nothing tells them a two-meter drop is ahead. They will roll straight off the edge.

Cliff sensors can fail even when present Even vacuums with cliff sensors may miss a drop if the sensors are dirty or the drop is dark-colored. Without them, failure is guaranteed eventually.

Physical barriers defeat the purpose You can use baby gates to block stairs, but that means you cannot let the vacuum run unattended. If your model lacks cliff sensors, keep it on a single floor or stay nearby.