What about 2 children who grow up in the same house, in the same environment and with the same parents.
Now, imagine the father is in jail and has been a drug user for most of his life.
1) The first child says "I will never be like my loser father." He works his ass off in college and lands a nice job. He has a family, house, car, etc...
2) The second son states "I had no role model. I messed up in life because of my father." He blames everyone for his issues. Parents, school, environment, etc.. He ends up just like dad. In jail.
It comes down to our decisions in life. Our decisions make or breaks our destiny. Does our environment count? Yes! But, it's not the determining factor. There are plenty of people who have risen from a bad environment to become successful later in life. There are also people who had money and a loving family. Yet, they got involved in drugs and overdosed. Bobbi Houston and Andy Reid's son comes to mind.