Skill and Luck
Some people take most of the credit for their successes and accomplishments even when external variables had more to do with the outcomes. But when things go badly, these same people will blame external variables and take little or no personal responsibility for what happened. This duality is possible because we often see causation where there is really just correlation or only see correlation where there is strong causation.
Of course other types of people, the kinds at higher risk for depression, tend to take the opposite outlook from the one just described. When things go well they attribute their success to any and all variables outside of themselves, and when things go poorly they take full responsibility, blind to all of the outside factors at play.
The ideal is to see reality for what it is, but we humans can be pretty bad at the endeavor and often feel compelled to put a spin on what happens to us, coming up with a plausible explanation and then running with it, even when this explanation is patently untrue or when access to more information would change it.
The answer from a psychological point of view is to determine which category you tend to fall into, whether you overweight your own contribution and underweight external variables or underweight your own contribution and overweight external variables, and then move your thinking a little bit more towards the middle. When we accept the role that chance plays in our endeavors, we are actually freed up a little bit to roll with the punches. We realize that what we do have control over is our own effort, that we can continue to improve upon our existing skills and to develop new ones. The more you put yourself out there without getting down when things don’t work out, the more you will expose yourself to the chance opportunities and lucky breaks that, combined with your hard work and talents, will eventually make good things happen.