Roberts 4 Rules off the top of his head for what it takes to be good at poker.

To be good at poker you need to understand the way people think.  

To be good at poker you need to be able to control your emotions; be an expert at anger management.   Not to get thrown off by people that throw people off.

To be good at poker it sure helps feeling comfortable bout the math.  Math is my thing yet I struggled early on with what was a correct bet size.  The guy betting 50 into 1000 pot.   Feel works too.  Once you get the hang of how much gets a call and how much gets a fold.  However at some point you are sliding out chips and it's a certain percent of what's in the pot.  In fact when I was poker on the television this is the most interesting part for me.  Saying out loud what I would bet in the spot and then watching what they put out.  Not that either answer is right.   There's also what your stomach can handle.  Like if we're on the turn and you're chasing a flush draw do I want to bet an amount that makes it incorrect for you to call to get you to fold and end the hand or do I prefer betting an amount that might get you to call so that I can try to win more money since I will win most of the time?  What players can't handle here are the times they are getting rivered.  That hurts too much and messes up #2 above.      

To be good at poker you have to be good at money management.  People vastly underestimate this last one.