DaveK - exactly, we agree on that - and hence my proposition that it comes down to ego.
Taking out novice stalkers, when we discuss safety I often use the example of having a self test question - ' Right now do I believe an accident wont happen because I'm that good or do I believe that an accident will happen and I need to be fully switched on'? Its an attempt to get across that may issues - safety being but one - are ongoing not a case of 'learning once'.
Its an old saw, but often true in reality - the most 'dangerous' shooters are the old ones who believe they know whats what, not the new ones who are really applying constant thought to doing the right thing.