Which malfunction could result from a failure to extract in a pump action firearm?

A failure to extract in a pump action firearm can indeed lead to a round being left in the chamber. When the extractor fails to grip the spent cartridge case after firing, the mechanism does not properly eject the casing from the chamber during the cycling of the action. This can result in the firearm being unable to chamber a new round, leaving the spent cartridge stuck inside.

This scenario can create significant issues, as the shooter may be unaware that there is a round still in the chamber, potentially leading to safety hazards if they attempt to fire without resolving the malfunction. Proper inspection and troubleshooting would be necessary to address this situation, ensuring that the extractor function is operating effectively to prevent such malfunctions in the future.