I don't see where this statistic controls for people who didn't graduate or for people who didn't take classes for which they would not be successful. This ave

I don't see where this statistic controls for people who didn't graduate or for people who didn't take classes for which they would not be successful. This average GPA could represent grade inflation. Or it could represent increased information symmetry between the difficulty of classes and the students themselves, paired with the students' interests, determination, and aptitude. TL;DR: Grade inflation or survivorship bias?