Finger off the trigger until ready to shoot is a lesson most people don’t get.
Holding a deadly weapon pointed at someone and your finger on the trigger means just a startled flinch and unintended squeeze of the trigger may be needed to kill.
Irresponsible gun owners make it difficult for everyone;granted irresponsible owners of other devices haven’t brought quite the same societal pressures(unless you count drivers’ licenses and mandatory car insurance).