How? The same way someone can hit the clutch instead of the brake, etc. People are not perfect. No matter how much we rehearse, practice, etc., absolute perfection is in this life an expectation that is guaranteed to be disappointed. Why do carpenter hammers have claws? You know. Even the best carpenters will bend some nails. Calling people who have AD/ND's stupid, etc. is pointless. When people from a wide variety of backgrounds engage in activity that is potentially dangerous, it is unreasonable to expect that sooner or later there will not be some sort of incident where a less than attentive individual accidentally discharges a firearm. Best thing everyone can do is just try to stay safe! Cheers!

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