Why did cutting up sea stars fail as a way to protect oyster beds?

Cutting up sea stars failed as a method to protect oyster beds because of the remarkable ability of echinoderms to regenerate lost or destroyed body parts.1

When captured sea stars were chopped into pieces and discarded back into the sea, they did not die; instead, they often regenerated into new individuals. As long as a portion of the central disk remained attached to an arm, the sea star could successfully regrow the missing sections. Consequently, this practice inadvertently increased the population of sea stars rather than reducing the threat to the oyster beds.1