They've fallen behind the rest of the West contenders
Looking at the landscape of the Western Conference, it's hard not to say that the Golden State Warriors haven't fallen too behind the rest of the contenders. Especially with the way the team has played recently. You can make the argument that the Phoenix Suns and Denver Nuggets are head and shoulders more talented than the Warriors. You can also say the Minnesota Timberwolves and Oklahoma City Thunder, who have a ton of upside, are beginning to show promise as a potential dark horse contender this season.
The Dallas Mavericks, Sacramento Kings, and even the Los Angeles Lakers are proving they're slightly better than the Warriors so far this season. Even if the Warriors can begin to play better over the next few weeks, it's hard to imagine them leaping over seven teams in the standings to emerge as a favorite to win the championship by the end of the season without making a roster-altering move.
Generally, by the time a team realizes that their championship window has closed, it's too late to salvage what's left of it. And the Warriors may be at the point. A team that has often prided itself on being "light year ahead," may finally find itself behind the rest of the contenders.