Backhaul is the path between nodes
Client devices connect to a nearby mesh point, but that point still needs a path to the main router. Wireless backhaul uses radio capacity for that trip; wired backhaul moves it onto Ethernet.
Wireless backhaul wins on installation simplicity
Wireless nodes need only power and sensible placement. It is the practical choice for rentals and finished homes where running Ethernet would be disruptive, provided each node can receive a strong upstream signal.
Wired backhaul improves consistency
Ethernet can reduce the effect of walls, floors, interference, and node-to-node distance on the backhaul path. It is especially useful for fixed offices, media rooms, and multi-floor homes that already have usable cabling.
Confirm the exact model supports the topology
Do not assume every point has Ethernet ports or that mixed generations can be hardwired together. Check the manufacturer diagram, port roles, switch placement, and whether setup must be completed wirelessly first.
Use wiring where it changes a real bottleneck
Wire the node serving the busiest or most difficult room first. If performance is already stable and the household rarely saturates the network, the installation effort may be better spent on router placement or one direct Ethernet run to a key device.