There are different ways to build a great basketball team. What makes one team successful won't necessarily work for another due to numerous factors.
In the same breath, there are plenty of ways to establish an elite NBA defense. The top NBA defenses use different approaches to achieve the same goal of getting stops. A team needs to be solid on both ends of the floor to win a championship, but a team that plays sound defense is usually more consistent, especially in the playoffs.
We can talk about defense for hours, but in this article, we’ll discuss the more broad aspects of defense, and how the best regular season teams approach them. If you look at the NBA’s leaderboard of defensive stats -- whether traditional or advanced -- it shows different teams with vastly different systems.
Here are the factors that are crucial for an NBA defense:
System and personnel
The coach's system and the players they have go hand in hand. Coaches usually base their defensive philosophy on their available talent.
Some coaches like going a more conservative or tactical route, forcing offenses out of the middle of the floor and towards the baseline and sidelines. Some like a more disruptive defense that plays into an uptempo style of offense -- getting steals and blocks then being able to push the ball up the floor.
No matter which system a coach prefers, the best ones adjust depending on the personnel they have. If you have an elite, intimidating big man that can protect the paint like Joel Embiid, Rudy Gobert, or Anthony Davis, you have more room to take risks on defense. Guards can be more aggressive in going for steals, knowing that they have a big man behind them to deter penetration.
The Philadelphia 76ers were one of the most disruptive teams in the regular season, thanks to having Embiid and a solid perimeter defender in Ben Simmons. They led the league in steals and were second in blocks per game. The Utah Jazz were also disruptive. Though they didn’t rank as high as the Sixers in steals or blocks, the Jazz allowed the least assists per game in the league, showing that they had a knack for throwing teams off of what they wanted to do on offense.
The LA Lakers, despite missing their two stars for nearly half of the season, still ended up with the best defensive rating. They did a good job of not allowing 3-pointers and rebounding. It was evident that they had a sound defensive system implemented by their coach, Frank Vogel. Other teams like the New York Knicks and Miami Heat also have defensive-minded coaches who implement effective strategies.
The most important thing that all these coaches have is their players’ buy-in. Probably the hardest part of coaching is getting players to believe in the system and execute it every game. The most consistent NBA teams have their players and coaches on the same page in terms of what needs to happen to get wins.
There are many more nuances to setting up a defensive system like how and when to deploy a zone defense, coverage on post-ups, and pick-and-roll defense. Each would need an article on their own to do them justice. 
Scouting and matchups
Teams often have coaches dedicated specifically to scout the opponents' tendencies. Knowing what a team and individual players like to do is a big chunk of playing defense.
For example, in defending someone like Ben Simmons who loves to go left, opposing coaches are going to want to force him to go right. One thing I love about the NBA is how teams almost always adjust the particulars of their defenses depending on their opponents.
Also, a key part of defense is being able to match up to what a team does. Switching on screens and pick-and-rolls has become the norm in the NBA and that's because teams have valued versatile players that can defend multiple positions. Switching, however, can only get you so far as some matchups are going to be bad for a team, like having a big guy try to cover a guard.
The Los Angeles Clippers in the last few games of their series against the Dallas Mavericks exclusively went small. The Clippers are uniquely equipped for this since they have several wings with size and speed that can cover Dallas star Luka Doncic. They often had to contend with having smaller guys on Dallas' bigs, but the Mavericks weren’t able to take advantage of those matchups.
In their ongoing series against the Jazz, the Clippers still have several options at center like Ivica Zubac and Serge Ibaka to match up against Rudy Gobert if needed.
Rebounding
One of the most underrated parts of a good defensive possession is rebounding. A possession only truly ends once a team gets the defensive rebound. Great defensive teams only give their opponents one shot per possession.
While offensive rebounds help get second-chance opportunities, I think it's more important to limit the opponent to one attempt at the basket. I don't care if you don't get a single offensive rebound, as long as we get all the defensive boards and limit opponents to just one shot per possession.
Does defense win championships?
Today, with the way NBA games are played, offense seems to be more favored. The top teams in the league score well over 100 points per game, with the Sixers leading the playoff scoring with 123 points per contest.
At the same time, the statement “Defense wins championships” always surfaces when experts talk about winning titles. One main reason is that it becomes more difficult to score in the playoffs. Team scouting and defensive preparation become more intense.
When teams meet each other repeatedly, coaches focus more on tendencies, which allow them to have a good grasp of everything the opponent likes to do offensively.
In a playoff series, it often boils down to the level of talent and how deep your team is. You’re going to need several guys to contribute to finding wins. While having great defense helps a lot, a team still needs solid offense to truly compete. It's all about finding the balance and getting the most out of your players.
In the end, scoring the basketball will always be a key part of the NBA game, but when the playoffs start, you better bring your “D” if you want to win the crown.
