I agree, people define success differently. To some people they may define success by material possessions/money, other may think of success in higher education and employment, others with family and others with religion etc. Having a PHD would mean nothing to a person that is happy raising a family. I think society in general puts too much pressure on people to go to Uni and get a good job otherwise you're seen as a failure (not true). Not everyone should have high expectations placed upon them because some people just aren't good at certain things.