Default [Q] Root Question

I had my phone rooted with towel root and the only thing I did was fix the hot spot provisioning so I can use Foxfi. I did a factory reset last night, and the weird thing is, I still have root and Foxfi still works. I figured that when I did the factory reset, I would have to reroot and fix the hot spot again.

I guess, I am wondering why that happened? It's good actually, saved me a half hour of work. But was that because I used the factory reset in the settings rather than through a reboot?

Please educate me. LOL