It takes luck to win a tournament, but luck doesn't always come in the form of a suckout. Basically, you win when you are consistently on the good end of variance. I'm sure you know that when you make a raise, call, or fold, you are making a decision against a weighted range of possible hands your opponent could have. Obviously the goal is to make decisions that are +EV versus that range. That may mean that Villains are consistently turning over hands at the low end of the range you put them on, or that your weaker hands are prevailing when Villains turn over hands at the top of their range. Of course, getting dealt good startings hands in the first place, getting moved to a good table, sitting in good position, catching blinds at the right times, having opponents win or lose key hands in which you are not involved, etc. are all elements of luck as well.