Traffic lanes can darken because of soil buildup, fiber distortion, oil transfer, shading, or a combination of those conditions.
Walking repeatedly over the same path changes pile direction and compresses yarn.
The altered fibers reflect light differently and may appear dark even after cleaning.
Soil from footwear and skin oils can also collect in traffic paths.
Professional cleaning may remove soil, but permanent crushing or shading can remain.
Robot vacuums can scratch hardwood and LVP if the brush roll or wheels are abrasive. Tile and carpet are safe for most robots. Use robots with soft brush rolls…