When you’re first starting out with a Zigbee network, it’s easy to misunderstand the way that the mesh actually works. You might think the more Zigbee devices that you add, the stronger the coverage becomes. As a result, you buy a ten-pack of battery-powered door, motion, and temperature sensors and place them all across your home, but then suddenly, half of them stop responding or go offline in Home a**istant. This is because battery-powered devices never route traffic or repeat signals. A house filled with 40 battery-powered Zigbee sensors has zero mesh resilience. If it lacks mains-powered routing hardware, understanding the strict functional boundary between Zigbee routers and end devices is the difference between a flaky smart home and a bulletproof automation network.