[product question] Why does the TO Niacinamide work as a spot treatment but not all over my face?

Beauty Tips For Body Care
Hi! I got a super bad breakout from cerave pm and I was trying to get rid of the bumps desperately so I tried TO niacinamide. Since it broke me out terribly before, I decided to spot treat with it and it actually calmed down my pimple very well. I’m confused as in why my skin hates it all over but it did wonders on one spot? Should I try using it as a last step in my routine (mixed in with my last product) to reduce irritation? Is zinc a pore clogging ingredient?
Girls Blog 2015
Submitted by usernameeee_