Well I can tell you both are required. And I mean quite a bit of both.

Also dont expect to make any serious money the first year and a half you play. It takes that long to get good enough to turn a profit at resonable stakes games (.5/1 NL and higher)

Sometimes the cards just dont run your way no matter how hard you try and no matter how well you play. Trust me I been playing a while now and just got thru a real cold streak. It happens. Good luck.