The Probability Behind Tanking in the NBA

The NBA has new trends arise every year, with the new innovations and play styles allowing teams to expand possibilities and change the game. These trends can become widespread in the NBA, such as the rise of three point shooting and more fluid player movement throughout the association. However, one of the most controversial trends that have come to the attention of fans and executives alike is the concept of tanking. Tanking in the NBA is widely recognized as intentional losing in order to acquire high draft picks and have a greater likelihood of drafting a superstar. The event that brought tanking to the forefront of NBA conversation was Sam Hinkie’s infamous stint with the Philadelphia 76ers, where he implemented the most public, outright tanking job in NBA history. Hinkie traded all of his top talents for future draft picks, improving the team’s chances of procuring a premium draft pick with a high probability of getting a superstar. The NBA has tried to prevent tanking with NBA Draft Lottery reforms such as the new format in which the top 3 picks all have the same chance of winning the number one overall pick. However, this has not stopped teams from trying to purposefully lose in order to improve their draft pick quality. But I want to know how effective tanking really is. What is the probability behind gaining a high draft pick and that pick becoming a great NBA player?

Tanking: The Process

Step 1: Losing

I believe that the process of tanking can be divided into 5 different steps: losing, getting good picks, drafting, improving, and winning. The first of these steps is losing. Obviously, no team wants to be stuck in mediocrity for a long period of time. The only ways to get out of extended mediocrity in the NBA are to either improve suddenly or decline suddenly. However, worsening a team is much, much easier than improving a team. Sudden improvement requires signing a talented player in free agency, drafting a star in the mid to late stages of the draft, or developing players enough so that the team improves as a whole. Therefore, many teams resort to intentional losing, trading away their top talents for future assets and clearing the roster of any old, expensive players. The next steps that the tanking teams can take is to gain more assets by taking on large salary cap hits.

In order to explore the history of tanking in the NBA, I gathered stats on all teams that have had three consecutive years with a win percentage below 0.400 (worse than 33-49 in an 82 game season). A total of 34 teams since 1979 fulfilled these criteria and can be considered as teams that tried to tank. Among the 34 teams, the ones with the worst three year record were the 2014-17 76ers and the 1999-2003 Bulls. The Trust the Process 76ers had a winning percentage below 0.2 while the post-MJ Bulls had a winning percentage of 0.217. These two teams lost as much as possible in order to secure the best chances of landing a top pick.

The 2016 Philadelphia 76ers, finished with a 10-72 record

Step 2: Getting Good Picks

After intentionally losing for the entirety of a season, the next step for tanking teams is to hope to get lucky in the draft lottery. With both the new and previous lottery system, the worst NBA team does not have a high chance of actually receiving the number one pick. Therefore, teams have to either get lucky or make up for bad luck by drafting better.

Step 2 is where the probability starts to come into play. The draft pick of a team is decided by the team’s standing and then the lottery results. Based on which lottery system is used, the probability of getting each picks differs. For simplicity, I will be using the new lottery system (worst team with 14% chance of getting number 1 pick) and the previous system (worst team with 25% chance of getting number 1 pick). The probabilities of placing at each spot based on the lottery system are shown below. On the top is the new lottery system, and on the bottom is the previous lottery system. As seen by the chart, the chances of getting a certain pick changes based on the lottery system. The new lottery system lessens the expected value of the pick for worse teams. For the worse five teams, the new lottery system gives a smaller chance of getting a better pick. In contrast, the teams that placed 7th through 14th got better odds of a high pick. The lottery ensures that losing doesn’t automatically guarantee a top pick.

The NBA Draft Lottery ensures that luck plays into teams’ draft picks. Some rebuilds can be bolstered by getting lucky, while others can be destroyed with bad luck. By using the expected value of drafting an All-NBA player based on each draft slot and each pre-lottery standing, the luckiness of a team can be found. The most lucky rebuild was the Cavaliers from 2010-13, who won the lottery three times despite never being the worst team. Meanwhile, the least lucky tanking team was the Sacramento Kings from 2009-13. They were one of the five worst teams four times, but only picks in the top five of the draft twice.

Step 3: Drafting

Drafting is the most important stage of the tanking process. Tanking in the NBA will not work unless the team can draft quality players can will develop into future superstars. Drafting a superstar is heavily influenced by the draft slot the team has, so I found the chances of drafting an All-NBA player at each draft slot. The actual results did not make complete logical sense (ie. the number 9 pick did better than the number 4 pick), so I smoothed the results with a logarithmic regression.

The lottery is very effective at reducing the effectivity of tanking as receiving the number one pick in the draft has the most success by a wide margin. The lottery provides an advantage for the teams that are not in the bottom 3, while giving a disadvantage to the worst teams. However, drafting in the NBA is never a given. It requires lots of scouting and resources. Having a good general manager that can take advantage of a high draft pick is paramount during the rebuild. Moreover, development is a key factor as the team needs to develop their talents into the best players they can become. About 25% of future All-NBA players become such players with a team that did not draft them, so making sure that an opportunity is not wasted by bad development is important.

The past tanking team that was the best at drafting All-NBA players was the Seattle Supersonics/ Oklahoma City Thunder in 2007-09. They drafted Kevin Durant and Russell Westbrook, leading the Thunder to a finals birth in 2012 and keeping the team in constant contention. The other two teams that were the best at drafting based on their picks were the Milwaukee Bucks from 1992-96 and the Portland Trail Blazers from 2005-07. The Bucks picked Vin Baker and Ray Allen, while the Trail Blazers picked LaMarcus Aldridge and Brandon Roy. On the other hand, the worst drafting team was the Bulls from 1999-2003. The 1999 Bulls rebuild was disastrous as they were stuck as one of the worst teams in the league for many years and they didn’t develop players properly. The Bulls drafted both Elton Brand and Tyson Chandler, each of whom became an All-NBA player on a different team. The Bulls are a prime example of why player development is crucial.

Durant and Westbrook led the Thunder to future playoff success after being drafted during a period of extreme losing

Step 4: Improving

The improvement stage of the tanking process consists of the development of the newly drafted players in addition to signing and flipping assets for quality role players or supporting stars. The improvement stage ideally comes after about three years, keeping the tanking period the most brief as possible. Teams should start to see their win percentage rise during the improvement stage, eventually getting to the playoffs and making a run for the championship.

The tanking teams had their winning percentage improve by 0.218 on average by the fifth year after the three year tanking period. The improvements ranged from -0.134 win% (by the 2007-10 Knicks, who actually declined after tanking) to 0.514 win% (by the 2014-17 LA Lakers, who signed LeBron James and flipped their assets for star big man Anthony Davis). Additionally, about 65% of the teams that tanked made the playoffs in their 5th year after tanking, and teams made the playoffs by their 2nd or 3rd year after tanking, on average. Tanking teams usually reached their peak by about their fourth year, as this would be the year that the drafted players would reach their primes and play their best. These stats suggest that the newly drafted players need sufficient time to develop and mesh together.

Step 5: Winning

The ultimate goal of any tanking or rebuilding team is to win the NBA championship. The teams should have their core players in place with several quality role players and a good coaching staff. But this is much harder than it sounds. Only a few teams that tank ever even reach the finals. While tanking teams expect the payoff of several years of losing to be an eventual title, few teams actually achieve this very lofty goal.

Only 8 of the 34 (24%) teams that tanked made the finals with the players acquired during the years of tanking. Only 2 of those teams won the finals. The two teams were the 2016 Cavaliers, led by LeBron James who signed as a free agent, and the 1989/1990 Pistons, led by Isiah Thomas who was drafted in 1981. Most teams only advanced to the first or second round of the players, at best. Some teams (15%) never even made the playoffs with their core at all. However, something that can be seen in the teams that made the Finals or won the championship is how their teams were built. Most of the teams drafted their superstar, except for the 2016 Cavs and 2019 Lakers (I’m classifying them as a finals team since they were 2nd in the NBA before the hiatus), both of which signed LeBron James as a free agent, and the 2002 Nets that traded for their superstar, Jason Kidd. The other teams, such as the Durant led Thunder, Iverson led 76ers, and Ewing led Knicks, drafted their superstar and surrounded them with quality players and a good supporting cast. Crucial players such as Westbrook for the Thunder, Motumbo for the 76ers, Laimbeer for the Pistons, and Irving for the Cavs, were acquired as secondary stars that helped lead the team to the finals. Throughout NBA history, only 0.2% of teams with 0 All-NBA players, 4.3% of teams with 1 All-NBA player, 19.5% of teams with 2 All-NBA players, and 20% of teams with 3 All-NBA players have won the title. Therefore, the it would be ideal for tanking teams to draft 2 All-NBA players. The rebuilds with the highest chance of drafting at least 2 All-NBA players were 2010-13 Cavaliers, 2014-17 76ers, and 1999-2003 Bulls, each of which had very good picks during their years of tanking. Winning a championship is the ultimate goal for all tanking teams, but only a few of them actually reach this level.


Tanking in the NBA is an effective way of getting out of mediocrity and eventually winning an NBA championship. Teams that have tanked do have future success, based on the 34 teams that have tanked before. Additionally, getting lucky and having good picks is important for drafting All-NBA talents. Teams such as the 2011-13 Cavaliers and 2014-17 76ers have had the best picks, meaning they had the best chances for future success. However, development is almost as important as drafting, as some teams (like the 1999-2003 Bulls) drafted All-NBA talents but couldn’t develop them into great players. Drafting is the most important part of the rebuild, with successful drafting leading leading the way for deep playoff runs. Some general managers pulled off the tanking, such as Sam Presti for the Thunder and Mike Dunleavy for the Trail Blazers, while others blew it, such as Jerry Krause for the Bulls in 1999-2003 and Elgin Baylor for the Clippers in 1994-98. The next step is surrounding the newly drafted talents with supporting players in order to improve and make it to the finals. Overall, 8 of the 34 teams (24%) that tanked eventually made it to the finals while 2 of the 34 (6%) won the championship. These promising numbers mean that tanking does actually work in the NBA today.

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