Spurs? The franchise that did one of the most blatant tank jobs in history to land one of the 10 greatest players in history who won at least 50 games every year of his career, went 5-1 in finals with said player, and have 0 finals appearances without said player. A franchise that has one of the longest playoff droughts in the sport now into their 7th year.
The entire Spurs culture was Tim Duncan. He was the winner. He is the one that got them titles and wins. They've been a mediocre franchise without Tim Duncan.
The Spurs won the Western Conference in 1994-95 (pre Duncan) and won 61 games in 2016-17 (post Duncan).
David Robinson & Gregg Popovich were military guys, Tim Duncan was malleable enough to fit into their military style environment. The Spurs ethos is that everyone is accountable and does their job.
The Spurs go for coachable players who understand their role. Go back and look at nobodies who have come through the Spurs development system, become high level role players, got paid elsewhere but were never as good.
Look at the Spurs coaching tree across the NBA. Heck look at the Oklahoma City Thunder and the environment they have built, that has all come from Sam Presti and his experience in San Antonio.
The Spurs are the New England Patriots of the NBA.