An Engadget explainer addresses the common habit of adding a second router to fix weak Wi-Fi, warning that leaving both devices in standard router mode creates a "double NAT" setup with two separate private networks. While this rarely slows ordinary browsing or streaming, it can cause problems for tasks like online gaming, port forwarding and UPnP, and makes it harder for devices on the two different networks (such as a computer and a printer) to find one another, even within the same home.

The article recommends alternatives depending on the need: a mesh Wi-Fi system for extending coverage seamlessly, switching a spare router into access point (AP) mode to use existing Ethernet wiring, or a simple Ethernet switch if more wired ports are needed without extending Wi-Fi. It also notes that ISP-supplied gateways can cause the same double NAT issue, and suggests either enabling bridge mode (to let a personal router or mesh system take over network management) or putting the personal router into AP mode while the ISP gateway continues routing.