Can't find a link, but there have been some studies on students and schools that show the students near the top of their class in not-so-great schools tend to be more successful than kids who are below average in elite schools, even if the latter have higher test scores. It really shows you the power of comparison and the importance of choosing the right pond for the size of fish you are.
And thus it is very wise to be grounded to the reality, however that is possible. Everyone is worse than me == superiority. Everyone is better than me == inferiority. Everyone does what they can and I should focus on what I can also, believing in myself and investing in my own growth == freedom.