The coaching carousel continues to spin in the NBA. In recent days, the Los Angeles Clippers -- coming off the best season in franchise history -- have decided not to bring back Vinny Del Negro as head coach. The Phoenix Suns -- coming off their worst season since they were in expansion team in the late 1960s -- have decided to turn to Jeff Hornacek to lead their team back to respectability. And the Atlanta Hawks -- who were essentially average this past season -- have turned to Mike Budenholzer to lead the team next year.
These are hardly the only teams to make a change. Since the end of the 2012-13 NBA season, the Brooklyn Nets, Charlotte Bobcats, Cleveland Cavaliers, Detroit Pistons, Milwaukee Bucks and Philadelphia 76ers have all decided that the person who coached the team at the end of this past season shouldn't be around for the next season. In all, at least nine of the 30 NBA teams will have a new coach next year.
These changes -- as I have argued before -- will probably not make much difference. A study published in the International Journal of Sport Finance (full PDF here) -- which I conducted with Mike Leeds, Eva Marikova Leeds and Mike Mondello -- found that most NBA coaches across a sample covering 30 years did not have a statistically significant impact on player productivity. And in other sports, we also have evidence that coaches cannot systematically change outcomes.
One would expect that coaches would disagree with these studies. Certainly a team is not likely to commit millions to a coach who claims the coaches really don't matter. That is why I was surprised to read the following from Brendan Savage of mlive.com a few weeks ago. The article includes extensive quotes from Jeff Van Gundy, a former NBA coach (and current television broadcaster) whose brother (Stan Van Gundy) is actively seeking employment as an NBA coach.
Without mentioning Joe Dumars by name, Van Gundy blamed Detroit's president of basketball operations -- and not Lawrence Frank, who was fired... after two seasons - for the Pistons' failure in the past few years.
Here's what Van Gundy had to say when asked about the recent NBA coaching changes that included Doug Collins resigning in Philadelphia and Byron Scott getting fired in Cleveland.
"Detroit Pistons basketball slogan: When the going gets tough, we fire the coach," Van Gundy said. "It's unbelievable. It's unbelievable. You know what surprises me, Chris? These new owners in Detroit have to be exceedingly bright to have made as much money as they have. And to be duped again that your G.M. tells you that the roster is good and the coach is bad ... what was the problem with Michael Curry? What was John Kuester? Now Lawrence. They run through coaches and they haven't even begun to address their problem. They have very little talent and very little basketball character. You combine that, you're going to be in a long rebuild.
I'm just surprised that when everybody acknowledges it's a player's league - everybody would agree with that - then the most important player or person in any organization is the person that picks the players. But we don't, as organizations, examine them. We just take the easy way out time and time again. You lose, the G.M. convinces the owner 'We got good players. It's the coach's fault.' We fire the coach; we bring a new coach in; we continue to lose. We fire that coach, saying that 'We have better players.' It just goes on and on. It's typical and I can't believe that the Detroit owners fell for it. I just can't believe it."
One suspects that the new owner of the Pistons "fell" for this story because this is the story coaches tell. NBA coaches are paid millions of dollars. To secure these contracts, one suspects that these coaches argue in the interview process that coaches are truly important.
But now we have a former coach (again, with a brother looking for work) telling a very different story. And again, I think the data supports what Jeff Van Gundy is saying.
As Van Gundy notes, the Pistons have recently gone through three coaches. And the Pistons have not had much success after these coaches came to Detroit. Before these coaches arrived, though, the Pistons were quite successful.
The difference, though, doesn't appear to be the coach walking the sidelines. When the Pistons were successful the team simply employed more productive players.
To see this, let's look back at the 2007-08 season. That year the Pistons won 59 games.
When we look at Wins Produced (calculation detailed here), we can see that most of these wins were produced by a minority of the team's roster.
The Pistons in 2007-08 (numbers from theNBAgeek.com)
An average player produced 0.100 wins per 48 minutes (WP48). Of the players who played at least 1,000 minutes in 2007-08, five players were above average. And these five produced 46.2 of Detroit's wins.
But since the end of the 2007-08 season, these players departed and/or aged. For example:
- Chauncey Billups -- who led the team with 15.0 Wins Produced -- was traded for Allen Iverson after a few games in the 2008-09 season. Iverson was never as productive as Billups in 2007-08, so this trade didn't help (something noted when the trade was made). One should note, Billups went on to have several more productive seasons with the Denver Nuggets (Iverson, though, was not very productive after the trade).
- Tayshaun Prince (8.6 Wins Produced) was 27 in 2007-08. NBA players tend to peak in their mid-20s, so as expected, Prince began to offer less and less as time passed (until he was eventually traded to the Grizzlies this past season).
- Antonio McDyess (7.8 Wins Produced) was part of the Iverson trade, but came back to the Pistons (at the age of 34) for the 2008-09 season. He then departed for the Spurs in 2009 (where his career ended after the 2010-11 season).
- Richard Hamilton (7.5 Wins Produced) was 29 in 2007-08. He did stay with the Pistons until the 2010-11 season, but not surprisingly, offered much less after 2008.
- Jason Maxiell (7.2 Wins Produced) was only 24 in 2007-08 and is still on the Pistons roster. And although he was still above average through the 2009-10 season, as he has aged he has also offered less.
For the Pistons to remain competitive, this production had to be replaced. And when Iverson's contract expired at the end the 2008-09 season, the Pistons had an opportunity to acquire productive talent in the free agent market. Unfortunately, the Pistons -- and specifically, this means Dumars -- decided to spend much of this money on Ben Gordon and Charlie Villanueva. At the time I noted that neither player had ever been very productive. And since this trade, neither Gordon nor Villanueva has been very productive.
Unfortunately for the Pistons, not only did the Gordon and Villanueva acquisitions fail to work out, the team also had trouble finding other productive players.
Again, the Pistons had five above average players in 2007-08. Here are ALL the above average players the Pistons have employed since 2008 (minimum 1,000 minutes played).
The list only includes eight names. Three of these players -- Maxiell, McDyess and Prince -- were on the 2007-08 team. As noted, these players aged and so their production had to be replaced.
Two more names -- Ben Wallace and Tracy McGrady -- were both quite old when the Pistons added each to the roster. So both could hardly be thought of as the sort of players the Pistons were acquiring to build for the future.
That leaves us just three names. Jonas Jerebko, Greg Monroe and Andre Drummond were all acquired in the draft. Of the 14 players drafted by the Pistons since 2008, these are the only players that have become productive players. So the Pistons have missed more than they have hit in the draft.
In sum, the Pistons -- since 2008 -- have not been adding enough productive players to contend. Joe Dumars -- as Jeff Van Gundy notes -- has been the person responsible for assembling these rosters. And he has also been the person who seems to believe that if he just finds the right coach, somehow these players -- who generally do not have a history of producing large sums of wins -- will become productive NBA players. But the data says this is unlikely. Basketball players tend to be consistent across time, and changing coaches doesn't often change what players offer on the court.
The good news is that the Pistons still have Drummond, Monroe and Jerebko. So the cupboard is not bare. But also, the team needs more.
Can Joe Dumars be counted on to find those players? Or is he currently looking for the next Gordon or Villanueva?
We don't know which players Dumars plans on adding. We do know that Dumars is currently looking for a coach. But as Jeff Van Gundy has argued, that is probably not going to make a difference. It is the players that matter. And until Dumars finds more productive players, fans of the Pistons (and yes, I am one of these) will continue to be disappointed.