In what circumstances will a court grant a motion to dismiss a first amended complaint?

In Indiana Public Retirement System v. SAIC, Inc. , 818 F.3d 85 (2d Cir. 2016), the district court granted in part and denied in part a motion to dismiss a first amended complaint. 818 F.3d at 91. In its decision, the court granted the plaintiffs leave to amend the claims that it dismissed without prejudice. See id. The plaintiffs did not file an amendment within the time allotted, however, and proceeded with their claims that had survived the motion to dismiss instead. Id . The defendants, meanwhile, moved for reconsideration. Id . The court granted the motion for reconsideration and reversed course. See id . On reconsideration, the court granted the motion to dismiss in full and dismissed all the plaintiffs' claims with prejudice. Id . It then entered judgment for the defendant. See id .