Why this police trainer avoids the words "try" and "don't"

Police trainer Brian Willis' advice on why we want to avoid the words "try" and "don't":

Why you should avoid the word "try"
"When you say you're going to try to do something, that allows for-even anticipates-the possibility of failure. The full commitment to accomplish what you say you want to do just isn't there, and your subconscious mind accepts the willingness to fail. That makes it easier to fail."

Why you should avoid the word "don't"
"When you start a sentence with the word 'don't,' your mind has to create an image of what you're not supposed to do. For example, 'Don't jerk the trigger,' 'Don't quit,' 'Don't stand still in the suspect's field of fire,' 'Don't panic,' 'Don't move.'"

"In imagining what not to do, your mind tends to drop the word 'don't' and processes the rest of the sentence and the image it conjures into your subconscious. This tends to propel you into repeating the same negative behavior over and over again."

"For positive results, you need to communicate what you want of yourself and others in positive terms: 'Press the trigger smoothly,' 'Keep fighting,' 'Move to the nearest cover,' 'Stay calm,' 'Stay still and listen to my commands.'"