Allow me to present some counter anecdotal "evidence." I have two brothers. We're all 6 years apart; I'm 21, the middle is 27, and the oldest is 33. We've ended up in vastly different situations due to a series of personal choices affected and limited by the environment we were given. The environment that one grows up in, even within their family, is such an important factor.
The amount of money and mobility my parents had, when my oldest brother was born, was an order of a magnitude less than what they had when I was born. As a result, my oldest brother's only option was public school in an underfunded district for grades 1-12. College was out of the qusetion, even if he could make it! On the other hand, my middle brother had the option to go to private school for grades 1-12, and graduated from University of Miami. For me, it was private school for grades 1-8, and when my parents were faced with the decision of sending me to the same public school my oldest brother went to, they moved instead to send me to one of the best public schools in the state. My oldest brother didn't have that option.
So when you see my oldest brother unable to hold down a moderately well-paying blue-collar job, and me working a low six-figure white-collar job, you can't simply say that one of us needs to "step it up." We are largely a product of the totality of our environment.