And remember that correlations are very, very rarely 100%. So even if there is a meaningful correlation between height and basketball excellence, height doesn't capture all of the factors that contribute to NBA success. For example, Isaiah Thomas.

Plus, regression to the mean. If you have two measurements, one of which is a fair distance off the mean, the second measurement is likely to be closer to the mean.

And big picture, the question of over/underachievement is less significant to an individual's outcomes than their capacity to make the most of the opportunities that come their way by exercising character skills.