The removeShard command is only checking locally in the config server if the removed shard does not own any more chunks, however, this check can pass right after the latest migration commits the chunk on the config server, but has not finished the cleanup, meaning that important persistency cleanup tasks like starting the donor shard range deletion, removing the recipient shard's range deletion document document and even removing the coordinator document, might never be executed if a user shuts down the shard immediately after receiving a successful result of a removeShard command.

Remove shard should check with the draining shard if all migrations are finished and successful.