With Kevin Durant and Kyrie Irving returning to the starting line-up, the Brooklyn Nets are one of the most exciting NBA teams to watch out for next year.The Nets recently hired 2-time MVP Steve Nash as their head coach and are looking to further upgrade their roster in the offseason. While they may seem like one of the favorites to win a championship soon, there are some problems brewing below the surface.Without further ado, let's take a look at 5 reasons why Kevin Durant and Kyrie Irving will not win an NBA championship with the Brooklyn Nets:#5. Kyrie Irving and Kevin Durant's lack of leadershipMilwaukee Bucks v Brooklyn NetsThis might come as a surprise for a team that has 2 bonafide superstars. However, even though Kevin Durant and Kyrie Irving have won championships in the past, they weren't the leaders of those teams.“I came in there wanting to be part of a group, wanting to be part of a family, and definitely felt accepted,” says Kevin Durant of his time with the @Warriors. “As time went on, I started to realize I’m just different from the rest of the guys.” https://t.co/knh5j8nnQ7 pic.twitter.com/M1orrozvpJ— WSJ. Magazine (@WSJMag) September 10, 2019Kyrie Irving was just 24 when he won his ring in 2016, and LeBron James was the leader of the Cleveland Cavaliers team.Although an argument could be made that Kevin Durant was the best player in the Golden State Warriors dynasty, it was actually Steph Curry's team. There were even reports suggesting Durant felt like an outsider despite being a key part of the Warriors group.#4. Brooklyn Nets' competitionMilwaukee Bucks v Los Angeles LakersAfter a decade of living with 'super teams', the NBA has now moved on to 'dynamic duos'. Even though Kyrie Irving and Kevin Durant will be among the best duos in the league, the competition has never been this intense in the past.Let's just look at the Western Conference: LeBron James and Anthony Davis, Kawhi Leonard and Paul George, Harden and Westbrook, Steph and Klay, and the list go on. Never has the league been so unpredictable in the past without any clear-cut favorites.These two. pic.twitter.com/y0VZSBeKcS— Los Angeles Lakers (@Lakers) September 27, 2020If you think the Brooklyn Nets will have their chance in a few years when guys like LeBron James are past their prime, think again. There are already a few young dynamic duos like Doncic-Porzingis, Murray-Jokic who will hit their prime in a few years' time. (We haven't even accounted for guys like Giannis Antetokounmpo, Jimmy Butler, and Joel Embiid in the East.)Also read: NBA Trade Rumors: The dream starting 5 for the Philadelphia 76ers going into the 2020-21 season