Preseason expectations for NBA teams typically remain stable well into the season; however, some teams are already prompting a reevaluation of those anticipations. Making strong conclusions around Game No. 15 can provide valuable insights, allowing for a closer look at both the top performers and those struggling in the early stages. This analysis will focus on the biggest winners and the most concerning losers, contrasting their current performance with earlier forecasts.

The Cleveland Cavaliers remain a highlight of discussion, even after losing their undefeated record to the Boston Celtics on Tuesday night. This defeat does not detract from the Cavaliers' strong start to the season and merely highlights their potential moving forward. The absence of key players such as Isaac Okoro, Dean Wade, and Max Strus, alongside an off-night from Darius Garland, did not prevent Cleveland from making a comeback from a 21-point deficit. The resilience displayed signifies their strong chance at remaining competitive. As their offense ranks among the best in the league, and with Garland's notable leap in performance alongside Evan Mobley and Donovan Mitchell's skillful playmaking, the Cavaliers are positioning themselves as genuine title contenders in the Eastern Conference.

Conversely, the New Orleans Pelicans continue to face injury struggles, with their injury report growing increasingly concerning. The team entered the season with uncertainty regarding upgrades at the center position and the future of star player Brandon Ingram. The ongoing injury issues have led to contemplation about potentially trading Ingram or CJ McCollum, but questions linger about the feasibility of effectively reshaping the squad. With the specter of 'Trade Zion!' looming, it becomes challenging to envision a clear path forward for New Orleans amidst the ongoing difficulties.

The Golden State Warriors have surprised many by assuming the top position in the Western Conference despite earlier skepticism regarding their roster's depth and talent distribution. The team's current defensive prowess and efficient offensive unit rank them among the best in the league. The decision to utilize Jonathan Kuminga off the bench and maintain a deep rotation of players has appeared successful so far. Although there are calls for a secondary scoring option alongside stars Stephen Curry and Draymond Green, the current structure may be effective enough to contend again this season, similar to the championship-winning roster of 2022.

Meanwhile, concerns are rising around the Milwaukee Bucks, whose struggles do not appear to be alleviated by Khris Middleton's absence. The offensive issues, paired with an average defense, have raised questions about the team's overall performance. While Middleton’s return is anticipated, the improvement path seems less clear due to their lack of athleticism and consistency. The Bucks’ existing roster struggles in critical areas, making it hard to envision a successful turnaround this season despite their potent offensive stars.

Finally, the Los Angeles Lakers' unexpected rise has attracted mixed reactions regarding the sustainability of their success. Despite being over .500, their defensive struggles and net rating suggests a need for further improvement to maintain their high standing in the Western Conference. Head coach JJ Redick has implemented changes in their playing style, with Anthony Davis emerging as a legitimate MVP candidate. While the roster shows promise, without any major trades or acquisitions, maintaining their momentum may prove challenging.

The Philadelphia 76ers illustrate the unpredictable nature of team dynamics, with key players Joel Embiid, Paul George, and Tyrese Maxey yet to share the court. Recent performances hint at significant hurdles — a subpar offense and defensive lapses continue to hinder their prospects. Despite the potential for improvement, doubts linger within the fanbase about whether the current trajectory will lead to desired success or if changes are necessary to become contenders in the Eastern Conference.