Bad Pilots
I agree with the preceeding. A good point brought up, talk money. This will cost you money, that will cost you money, funny things like liability issues, planes hitting the sides of mountains may make some impact, but from my personal experience, bring up the cost, gee whiz and watch thier eyes light up. That's how I get thier attention.
So much for right and wrong, doing the right thing, and all that...