Commonly franchise success in NBA is defined by how many NBA titles a team wins or more simply if a team wins the NBA championship in any given year. Others may choose to look at how many times a team qualifies for the playoffs or the team win% as any one NBA playoff series has potential to be influenced by the effects of luck/injury etc small sample size series. That said, let's look at the year over year consistency of teams to see which teams have long term success rather then only focusing on NBA championships. To do this, we can plot the team Win% vs the Consistency (Standard of Deviation of Win%) over a specific period.
Franchise Success Over The Past 5 Seasons
Below I plotted Win% vs the Consistency over the past 5 seasons from 2008 to 2013. Observing the y-axis (Win%), we see that over the past 5 seasons we can see the Spurs have been the most successful team with a 69.3% Win%. This contrasts to the Timberwolves who have won 28.7% of their games over the past 5 seasons. As a special note, the mid-band rectangle shown around 50% represents the "treadmill teams" which over the past 5 seasons have won approximately half of their games (Pacers, Knicks, Phoenix, Pelicans, Cavs, 76ers, Bucks etc). [Right Click and Open In A New Tab to see a larger view]
Franchise Consistency Over The Past 5 Seasons
The y-axis plots Consistency (standard of deviation of Win%). Think of this as how much variation exists in the Win% over the past 5 seasons. For example, Washington and Denver (Masai past team) have good consistency ratings of 4.5% Denver 4.6% respectively. That is, to say, that over the past 5 years Washington's Win% standard deviation in Win% has been 4.5%. And we can see given their near league low Win%, that they have been consistently poor team. This contrasts to the Nuggets who have been one of the consistently successful team. On the opposite end of the spectrum are the Cavaliers with a consistency score of 27.3%. Over the past 5 years, they have gone from the playoff thrills with Lebron James to lowly basement tanking. However, given their Win% is 48.5% in this 5 year period they are effectively a treadmill team. That is, to say they inconsistent but average team.
Win% vs Consistency Over The Past 5 Seasons
The horizontal and vertical red lines shown represent the average Win% (50%) and average consistency (11.1%) of deviation of Win%) respectively. The circle, is thus the "average" team that treadmill with average year to year variation in standings. The Pacers, are the epitome of the "average" NBA team who are not great nor that bad in any given year. The upper left quadrant is desired state for most NBA teams as it represents both long term success (Win%) with good consistency. That is, teams that year in and year out are competitive. The Spurs and Denver are ideal examples of these consistent "good" teams. The upper right quadrant represents teams that are more often winners then losers but can have more wild swings in fortunes. Teams in this quadrant may exemplify teams that "tank" successfully. For example, OKC and perhaps Orlando (though the Magic results are reflecting the past Dwight Howard success and are not predictive). The lower right quadrant represents teams that are more often losing teams then winning teams but they also have wild swings in fortunes. (That is, inconsistent poor team). Teams like the Bobcats and Nets are shown and to a lesser extent the Clippers. These may potentially show teams that have tanked over the past 5 seasons but have not been successful (Bobcats). Or in the case of the Nets a team that is great one year and terrible the next with little rhyme or reason. Again these are not predictive of the future success of the franchise. And finally the lower left quadrant represents teams that are good at being bad or who have consistently lost over the past 5 years (consistent poor teams). Washington and Sacramento are examples of these teams who have won few games in each season over the past 5 years . They have also potentially drafted, traded and retained talent poorly.
The Raptors and Other Teams
And finally the Raptors by this analysis appear to be a consistently poor team. They of course have had some playoff success in the past 5 seasons however, compared to other teams across the league they have been "better" at losing consistently. Of course, not as poorly as the Kings or Wizards and not as well as average Pacers. As stated previously, this is not necessarily predictive of the Raptors future. With Masai at the helm, they may move more towards the Nuggets style of a consistently good team. However, we should not even though the Nuggets are a better team as measured by consistency have had limited playoff success. Finally, Miami is another interesting team who is trending towards the upper left quadrant since the addition of Lebron and Bosh. In a few more years provided the core remains healthy and together they may supplant the Spurs who will have a challenge filling in for the decline and eventual loss of Duncan.
A Longer View Of Consistency (9 Seasons)
The above 5 year is rather arbitrary but lines up generally with the tenure of GM. Below is the same plot looking at the past 9 season from 2004 to 2013. 9 seasons was chosen for simplicity as it represents when the Bobcats entered the NBA as an expansion team. This plot is not annotated as the previous example, however the "average" team is plotted and again, we see that Spurs and Denver are some of the more consistent successful teams. That Miami represents an inconsistent successful team. This view doesn't show an ideal inconsistent "losing" team. Rather, what we see are teams like Memphis, Atlanta, Nets, Cavs and Pelicans remain "treadmill" team especially when contrasted with the 5 year view. That is, it is difficult to find evidence that "tanking" will lead to more then treadmill mediocrity. And finally the Bucks and Raptors over the past 9 season represent "consistently poor teams".
An Even Longer View Of Consistency (18 Seasons)
The final plot of consistency is over the past 18 season which was chosen because it lines up with when the Raptor and Grizzlies entered the NBA as expansion teams. This timeframe also represents the life time of an elite player like a Duncan or Nowitski however they may not remain on the same team and provided the start date lines up with when they enter the league. At any rate, not much is new or surprising as again Spurs (and Lakers) are shown as one of the most consistently good teams the past 18 seasons. Teams like Utah, Houston also show up well over the 5/9/18 year view but they are the "bridesmaid" type teams and rarely NBA champions. That is, above avearge teams but often lacking that one player to take them over the top. This view also shows Denver as a poorer and inconsistent team over the longer time frame (locked in the treadmill). Finally the Raptors, Bucks, Bobcats, Warriors and Wizards are again "inconsistent poor" teams. And the Grizzlies who have been as unsuccessful but have had much more variation in their success.
Some Unscientific Conclusions
- Some teams can attain consistent long term success (Spurs/Lakers)
- Those long term successful teams with an elite franchise player like Kobe or Duncan can achieve better playoff success however those elite players are surrounded by very good secondary players.
- Since 1995 some consistent long term successful teams like the poor Nuggets, Utah, Phoenix, Pacers and Houston have remained the 'bridesmaids' And related, having a franchise player doesn't guarantee a championship as Nash didn't produce much more then an above average consistent team for the Suns.
- Some teams are can consistently fail over the long term (Raptors, Wizards) likely because of management/ownership incompetence? as they should gravitate towards "average"
- Most teams are mediocre treadmill teams but some are consistent (Pacers, Knicks) and others more inconsistent with wilder swings in failure/success but still an treadmill team.
- Very few teams are inconsistently "bad". That is teams are more likely to be inconsistently average and less frequently inconsistently good team after they "tank" or rebuild. That is, a team that tanks or is very bad one year is more likely to become average then long term successful.
- Very few teams appear to move out of their long term zones. The Nuggets are an example and Miami maybe another (however they are still in their long term area). Said differently, consistent good teams remain consistently good. Consistently poor teams remain consistently poor. Bridesmaid teams remain bridesmaids. And Treadmill teams remain mediocre. This maybe a reflection of ownership and management skill.
- Tanking doesn't seem to build consistent winning teams over the longer term.