Cutting out queen cells is not a good way of preventing swarming, it is, however, a very good way to go queenless. If you had numerous open swarm cells it is possible that the hive issued more than one swarm. Bees often swarm several days before the new queen hatches, cutting out the queen cells after they are capped may mean the bees swarm and there is no new queen to replace her.
If you observe unhatched swarm cells it is much better to do a split rather then cut out the cells. That way you get 2 queenright hives. When doing such a split remember that to simulate the act of swarming it is best to move the queen to the new hive and let the new queen take over the old hive.