Hey, it's bound to happen, right? Laws of probability. You got x number of athletes in a space that's y feet long by z feet wide. You have an average of q number of passes per game, r number of shots, s number of rebounds and t number of deflections. Then there are b number of instances of daydreaming (always a contributing factor), and c number of intentional, hot-tempered facially-directed lobs. It all adds up, folks.
Proof is in the slides that follow.