Basically this; remove 10 nodes quickly, and one will remain on board most of the time.
Recently, I tested this issue by quickly adding and removing 81 nodes of all types, including roots and port keys, on a 9×9 board. 6 replicators and a root node remained on board, then disappeared upon testing.
That doesn’t mean that it can’t happen to the other types of nodes, these are just confirmed to be affected by the glitch.