Speak gruffly to a dog using their name and their name becomes a ‘poisoned cue’. Come home and reprimand your dog because they chewed your shoe and your coming home becomes a ‘poisoned cue’. You may not even be aware of what your dog associates with the punishment.
When you have challenges with your dog’s behavior it may be because you’ve poisoned a few cues by using punishment to change their behavior.
Mary’s dogs try hard to get it right. If they’re not getting it right, think twice before you raise your voice or yank on a leash. You may need that cue you’re about to poison.