In the NBA, nothing is guaranteed.
Sure, right now, it seems like the Boston Celtics got the best possible outcome out of the LeBron James sweepstakes, as he's heading west and clearing a path for the Celtics to get to the finals just as the formerly rebuilding franchise morphs into a title contender.
With James in the East, the Celtics have struggled to advance since the last contending Boston team sent a baby LeBron packing a decade ago, so why would James heading to the hellscape that is the NBA's Western Conference potentially create any negative outcomes for the Celtics?