Keeping the band together: On NBA continuity rates

We finally did it. Basketball season is so Stromile Swiftly approaching that I can almost feel the buzz of my phone, filled with texts asking if I’m watching Kyrie Irving turn a defender into stir-fry. I can almost see the VICE Sports column describing some well-meaning human’s attempt to baptize their baby in the waters of Klaytheism. I can almost hear the strained disappointment in Mike Breen’s voice as he discusses Walt Frazier’s sartorial selection of the evening during the fourth quarter of the Knicks getting blown out at home.

With less than a month to go before the beginning of the NBA regular season, the cavalcade of predictions, projections and presumptions has begun to push its way through the door, soon to blindside us with the innumerable stray ideas that looking at a new roster amidst new rosters brings. The obvious switches are certainly the most intriguing and may be the hardest to accept: Kevin Durant going to Golden State, Dwight Howard heading home to Atlanta, Al Horford shipping up to Boston and the like. Similarly, we say goodbye to the likes of Kobe Bryant, Tim Duncan and Kevin Garnett, indelible figures with infinitely lengthy legacies in the NBA. Nothing lasts forever.

As Durant’s move in particular proved, players are increasingly able to take control of their own careers. The salary cap boom and the general evolution of the collective bargaining agreement has bestowed players with an unprecedented amount of agency, which the players themselves have used to form alliances with off-court friends or join contenders from the bowels of irrelevance. A good example here being LeBron James’ string of two-year deals, with the second year being a player option. Opt out, ad infinitum, survey landscape in the interests of both yourself and the rebounding mechanisms you surround yourself with, re-assess contract situations, repeat.

But what of familiarity? Even for as much as we hear about locker room fraternization, or a lack thereof, camaraderie can be underrated and undervalued as a team-building commodity on the surface, and even in situations like Golden State’s with Durant right now, in which every party is saying the right things about sharing and team success being greater than the individual displays of brilliance we have come to expect, the truth is that we do not know how new additions disrupt the status quo until we see it in action.

With that in mind, NBA.com advanced stats writer John Schuhmann sent off the below tweet on Wednesday showing expected values for roster continuity, which Basketball-Reference and Schuhmann’s tweet both list as the percentage of a team’s minutes filled by players from the previous season’s roster.

Basically, what we have here is employment turnover. Curious eyes will first note that Cleveland and Golden State each share slots right in the middle of the pack, and right next to each other. With the seemingly inevitable addition of J.R. Smith to the roster, Cleveland would jump nearly twelve percentage points and nine ranking slots.

Also in the interest of curiosity is that Portland returns the highest percentage of on-court minutes from last season. That stands in stark contrast to returning the second-lowest percentage last year, with its 47 percent coming in higher than only the New York Knicks’ 42 percent. Brooklyn, predictably, shows up in a distant last, though with Kenny Atkinson arriving from Atlanta, the biggest change may very well end up being in the coaching seat.

To examine roster retention as a factor in success, I turned to my good frenemy Microsoft Excel. From the NBA’s merger with the ABA in 1977 through this past season, I have listed the NBA champion and its continuity percentage as well as the league leader in continuity percentage and the league average as well as the difference between the NBA champion’s retention and the league average.

A deeper dive into roster continuity since the merger reveals a few interesting trends. Some, you may expect. For instance, between Duncan’s selection in the 1997 NBA Draft and last summer, the San Antonio Spurs had the highest average roster continuity of any team in the league, at 77 percent. The lowest over that time? The New Orleans Pelicans, who moved to the Crescent City in 2002 as the Hornets, with 59 percent on average.

As Basketball-Reference has it, the Pelicans franchise dates only to the move from Charlotte. The current Charlotte franchise retains the retention numbers of the previous iteration of the Hornets franchise as well as the Bobcats, but if it took only percentages from 2004-2015, the Bobcats/Hornets still have a slightly higher retention average, at 61 percent.

The greatest American team sports dynasty of the last decade and a half, the Gregg Popovich-led Spurs have prided themselves on building around pieces already in place. Even with Duncan retiring, the organizational structure in place is one that fosters loyalty and mutual respect among its players; the introduction of LaMarcus Aldridge a season ago is an outlier as far as big-name free agency signings go in San Antonio. Naturally, he fit like a glove last season, ensuring 50-win seasons for at least another decade, probably.

Generally, we see that championship teams turn in higher retention rates than the rest of the league – a just over 12 percent higher on average. Championship squads return about 80% of their previous season’s minutes to the total league average of 68 percent. In all but five seasons, the championship team had most of the necessary pieces in place already, at least relative to the rest of the NBA.

The exceptions deserve their due credit:

-Following the merger, the Portland Trail Blazers acquired Maurice Lucas and Moses Malone in the dispersal draft.

– The Lakers drafted Magic Johnson, who ended up averaging over 36 minutes per game, in 1979.

-Malone pops up again in 1982, when the Philadelphia 76ers signed him and traded for Caldwell Jones.

-The 2005-‘06 Miami Heat grabbed a disgruntled Shaq from the Lakers, ushering in Kobe’s age of heroball and giving Shaq, albeit temporarily, the edge in rings.

-In what is the lowest retention percentage (50 percent) by a champion over that period, the Celtics heralded the modern age of the non-homegrown Big Three in 2007 by bringing in Kevin Garnett and Ray Allen to play alongside Paul Pierce, promptly setting a record for win improvement from one season to another and charging to a title.

Equally notable are the teams that retained to their own detriment. The 1980-81 Denver Nuggets, for example, won 37 games and missed the playoffs, yet gave all of the following season’s minutes to the same players and somehow managed 46 wins as well as a playoff spot.

Mostly, though, it helps to bring back more players than other teams do. In addition to the Duncan-era Spurs leading the league in retention, many other notable teams keep the band together better than the rest. The six championship Jordan squads averaged a whopping 90 percent retention, leading the league in both 1992 and 1997. For a guy who enjoys gambling, Jordan does not seem to have liked taking chances with his teammates.

Golden State owner Joe Lacob caught some justifiable Internet heat following a New York Times profile this past March in which he espoused the virtues of venture capitalist theory with regard to running a basketball team. One of the central pillars of Silicon Valley is purposeful disruption, going against a stated norm in order to shake up the status quo and push everyone to higher bounds.

Sam Hinkie gave this his best run by driving a franchise directly into the ground for years, and only now are we seeing some vestiges of return. By signing Kevin Durant, the Warriors did not tear down everything to start over, but they shook up enough to put axioms of “too much of a good thing” and “if it ain’t broke” to the test.