Luck (or timing, or circumstance) is a big factor. But we're all responsible for creating circumstances in which we can benefit from luck. I think that's where the "showing up" tendency is so huge. You have to show up everyday, even when shit ain't happening, to benefit from serendipitous events. More rigorously, you have to optimize your payoff function (in the Talebian sense) so that you can benefit from luck for reasons other than pure chance.