Cost, and control.

I want to own my stuff. And I want direct control over it. I want it to do exactly what I want, when I want, how I want. I'm sick of paying monthly rental charges, and I'm sick of companies making changes to services that negatively impact my experience.

My hardware, my software, my rules. Simple as that really.

Mikrotik CRS326 are pretty cheap even brand new.

I use these all the time at work, decent bit of kit.

There's also the CRS310, but that doesn't have many ports.