The Spurs are number one in the league in defensive percentage, even ahead of the Warriors. Kawhi Leonard is the main reason for this advantage over the number one team in the Western Conference. The Spurs also defend the three-point line at a excellent rate as well. The reasoning is simple, Leonard is the best defensive player on the best defensive team in the NBA.
Leonard is having an MVP-like year, helping the Spurs to a 60 plus win record this season. This historic year for Leonard just happens to coincide with spectacular years from James Harden and the new triple-double master Russell Westbrook. This will likely mean that Leonard will have to wait another season to garner the award, but the voters could see the Defensive Player Of the Year award as a consolation prize for him. The award by no means would be charity because he has the defensive numbers to justify a selection.
1) Perimeter Oriented League:
Big Men like Draymond Green (Steal leader) and Rudy Gobert (Block leader) are definitely candidates for the award but when you consider that the NBA is so perimeter focused Leonard’s skill-set becomes more valuable. The defensive role of the bigman has diminished a bit in the last few years because the league’s best players score from the outside. Leonard guards the opposing team’s best player every single night and that's extremely valuable in today’s game.