Intentional Fouls and Innovation

When an NBA team gets the ball at the end of a quarter, their strategy is hardly a mystery. The team will hold the ball until the clock runs out and try and score on an iso-play. What the defensive team should do is a lot more complicated. Conventional wisdom says that the defending team should play ferocious D and merely hope the other team doesn’t score, but there is a better strategy.

If a team is defending at the end of the quarter where the other team received possession of the ball with between 6-30 seconds left in the quarter, they should intentionally foul. Specifically, NBA teams should be intentionally fouling the opposing teams worst free throw shooter.

The average NBA team scores 1.067 points for every possession they have. Although the average NBA free throw percentage is around 76%, I’m going to pretend the average free throw percentage is only 70% because the team would only be intentionally fouling the worst free throw shooter on the court (likely to be below average).  By giving two guaranteed free-throws to the other team, they will be giving up an estimated value of 1.4 points (two free throws with a 70% chance of going in) rather than the 1.067 they could be giving up by playing defence. However, by intentionally fouling, the defensive team is creating an additional possession for themselves at the end of the quarter.

By creating an additional possession at the end of the quarter, the defending team is giving themselves another opportunity to score. Using the average NBA expected point per possession number, the team has now created an estimated value of 1.067 points that they did not have previously. This means that even by intentionally fouling – increasing the opposing team’s expected point value by over 130%, you are still coming out ahead.*

1.4 (points given up by fouling) – 1.067 (points expected to give up without fouling)= -.33 points

– the expected value from an additional possession subtracted from the increase in points allowed is (1.067-.33= .737 points).

By intentionally fouling at the end of quarters, the defensive team is increasing their expected point value by .737 points.

There are three quarters in a basketball game where this strategy is possible. Because the chance of having the ball at the end of a quarter is largely a matter of luck, lets assume that NBA teams already gets possession 50% of the time or 1.5 times per game. This means that even if this situation took place every quarter, a team could only increase their end of quarter possessions by 1.5 per game. Because the timing of possessions does not always work out like this, lets assume that teams can use this strategy only once in 50% of their games. That means that an NBA team could increase their average point differential by .37 points per year.

Such a change in point differential would lead to the average NBA team winning an additional 2.3 games per year (using the Pythagorean wins formula).

For context – an NBA win is valued at benefiting an NBA franchise around $1.94 million dollars, thus giving a team an increased value of $4.462 million dollars per season.

The point of me writing about this was not to argue that NBA teams should start doing this (which they should), or even to spread this idea (its not a secret), but to highlight the recalcitrance to “weird” innovation.

Even if the numbers are slightly different from mine, this strategy is clearly effective and worth implementing. However, no NBA teams utilize this strategy. The only coach who has ever implemented such a strategy is Gregg Popovich, and he has done so only sparingly. Even so, it is not surprising that the coach regarded as being the most innovative, unique and smart is the only one with the fortitude to go through with such a strategy.

NBA teams are not stupid. NBA teams are cognizant of this issue and run various other strategies known as “two for ones”, where they try to time their shot selection at the end of quarters to increase the chances of receiving the last possession.

No NBA team intentionally fouls at the end of quarters (even though it is in their interest to do so) because it is counter-intuitive. Even if the General Manager in a team’s front office recognizes it as a good idea, they then would need to convince the coach. Even if the coach thought it was a good idea, they would then need to convince the players. If the team actually did implement it, the fans and media would ridicule them if it ever went wrong.

Even when innovation has clear benefits, the ability for people to dismiss an idea because its new, counter-intuitive or “weird” is substantial. For innovation to take place, its benefit must be larger than its level of “weirdness”. In the case of intentionally fouling, its utility has been outweighed by its “weirdness” and will not be implemented.