I run two routers at home, and it's not for the reason you think
This title could be clearer and more informative.Try out Clickbait Shieldfor free (5 uses left this month).
Running a second router behind your ISP's unit creates true network segmentation at home. The ISP router handles the edge connection while a personal router provides full control, its own subnet, DHCP, and firewall rules. Key benefits include isolating untrusted devices (IoT, guests) on the ISP network and containing home lab experiments to prevent accidental damage to trusted devices. The main downside is double NAT, which complicates port forwarding and some VPN protocols, but can be resolved by putting the ISP router into bridge mode.
Table of contents
The ISP router isn't really your routerKeeping untrusted devices isolatedReducing the "blast radius" of your home lab accidentsRunning two routers has its downsides95 Impressions