The L button’s light going off reminds Will that if he chooses to get out of the elevator and follow through with killing Riggs—something even he conceptualizes as a “loser” move—his own light (his life) will, at some point, go out too. The novel’s ambiguous ending means the reader is left to decide what Will is going to do. Regardless of whether Will’s new perspective does lead him to abandon the Rules, readers will hopefully be encouraged to undergo the same kind of thought experiments in difficult situations that Will underwent in the elevator.