Adversarial: A college basketball player who wants to get drafted early and signed to a big contract grows his hair up, so that NBA teams will measure him as being taller (up to the top of his hair).

Height is correlated with basketball ability.

Regressional: But the best basketball player in the world (according to the NBA MVP award) is just 6'3" (1.91m), and a randomly selected 7 foot (2.13m) tall person in his 20s would probably be pretty good at basketball but not NBA caliber. That's regression to the mean; the tails come apart.

Extremal: The tallest person on record, Robert Wadlow, was 8'11" (2.72m). He grew to that height because of a pituitary disorder, he would have struggled to play basketball because he "required leg braces to walk and had little feeling in his legs and feet", and he died at age 22. His basketball ability was well below what one might naively predict based on his height and the regression line, and that is unsurprising because the human body wasn't designed for such an extreme height.