What is a key characteristic of malfunctioning firearms?

A key characteristic of malfunctioning firearms is the inability to discharge a round. This typically occurs due to issues such as a failure to feed, fire, or eject properly. When a firearm malfunctions, it may simply fail to fire at all, which can be attributed to several factors, including mechanical failures, ammunition issues, or even user error. This characteristic is particularly concerning for operators, as it renders the weapon completely ineffective in a critical situation.

While increased rates of fire, inconsistent accuracy, and decreased recoil can be symptoms associated with certain firing conditions or specific ammunition types, they do not universally define malfunctioning firearms. The inability to discharge a round, however, is straightforward and clearly indicates that the firearm is not functioning as intended, making it the most accurate answer in this context.