Originally Posted by masameet
Anyway I'm guessing it's more of a fear of the firearm. Think about it: Some hunk of metal that seemingly and magically explodes in the hands ... Who wouldn't be scared of such potential harm?
Once a shooter understands that the firearm will explode in his hands and not hurt him; is taught proper stance, including maybe having his instructor place a hand on his back to remind him to lean forward; and becomes comfortable with the firearm and its recoil, he'll dispense with the fear and stop leaning backward.
This. My first instinct is to say that it can often be a fear of the firearm.
In my personal observations, many beginning shooters will hold the firearm out like it's a stinky diaper and some will even slightly turn their faces away from it. That seems to tell me that they're somewhat scared of the "bang!" that will occur.
I am certainly no instructor or expert shot; but, like masameet suggests, I help other novices like me by placing my hand on their backs to help them remember to stay forward and it works like a charm.