I know when I got Kalani I thought he didn't have a clue but then realized that I was giving him too much freedom and treating him like my older one, Hoku. So, I went back to basics - limited area, lots of praise, special potty treat - and all of a sudden he figured it out
I think it helped that I kept Hoku in there with him so he learned very quickly that pottying in the right place got him a yummy treat and some run around time in the living room!