Rummy FAQ: Can an Empty Slot Be Useful?

An empty slot is space not committed to a group. It can be useful because a future card may fill it in several ways, but it can also hide a problem when no believable route exists.
List cards that could improve the slot and consider how many turns remain. Multiple realistic connections indicate flexibility; one exact completion indicates a narrow plan. Surrounding cards matter too. A flexible slot is less valuable if keeping it forces you to hold expensive leftovers.
Keep some room for new information, but do not treat flexibility as a goal by itself. Commit when one route becomes stronger than alternatives or when final decisions approach. Set a review point so the slot does not become an excuse to wait forever. Reassess it after every important draw.