The Day Bol Bol Fell

Roots in risk aversion drop the NBA lottery talent to the second round.

Posted Jun 21, 2019

Photo by Alex Perez on Unsplash
Source: Photo by Alex Perez on Unsplash

Bol Bol is a gifted basketball player. He is seven foot two inches and provides a mixture of shot blocking and shooting that many NBA teams covet. Bol averaged 21 points, 9.6 rebounds, 2.7 blocks, and shot 52% from three-point range in his sole college season. Draft analysts expected him to be taken in the first round of the 2019 NBA draft.

Instead, Bol had the unenviable position of being the last player in the green room. He had to wait until the Miami Heat drafted him in the middle of the second round at 44th overall. He was then immediately traded to the Denver Nuggets. #NBAtwitter was up in arms. How could the talented center fall so far?

Risk aversion fells Bol. In a previous article, we discussed two factors in decision-making: mean expected value and outcome variance (i.e. risk).

This year’s NBA draft cohort is believed to be deep, with many individuals projected to contribute to NBA teams for seasons to come. Outside of a few exceptions like Zion Williamson, most players in the draft were seen to be fairly similar talents. This meant the perceived mean expected value was comparable for most of the draftees.

Bol Bol was one of the exceptions. Many see a path for him to be a very good NBA player. His mean expected value is probably higher than most players taken before him in the draft. But many are also concerned he could become a complete bust and not be an NBA player at all, offering little to no value to the team that drafts him. That outcome variance was too much for most teams to take on. 

A distaste for risk runs deep in human psychology. In a 2014 paper, Ruixun Zhang, Thomas J. Brennan, and Andrew W. Lo demonstrate that this aversion to risk has evolutionary roots. We are hardwired to avoid risk if we can.

At his best, Bol Bol could be a basketball “unicorn” like Joel Embiid or Kristaps Porzingis. But his injury history, slight frame, and concerns about his love of basketball make his downside risk extreme. Most teams weren’t willing to take on that kind of risk. This was especially true considering humans can be even more risk averse when making decisions for other people. Unlike many of us armchair GMs, team executives did not want to put their staffs through the process of dealing with such a high risk pick.

Bol Bol falling to the Denver Nuggets could be a good thing for his career. Denver is expected to be a good team next year and don’t need him to perform well right away. They are one of the few teams that are able to wait to see if his “upside risk” pans out, and can jettison him off their roster with minimal damage if his “downside risk” proves to be true.

Hopefully he proves to be more Spiderman than venom.


Batteux, E., Ferguson, E., & Tunney, R. J. (2019). Do our risk preferences change when we make decisions for others? A meta-analysis of self-other differences in decisions involving risk. PloS one, 14(5), e0216566.

Zhang, R., Brennan, T. J., & Lo, A. W. (2014). The origin of risk aversion. Proceedings of the National Academy of Sciences, 111(50), 17777-17782.