Mixed messages can spell doom for the credibility of a speaker. The most obvious example is contrasting verbal and nonverbal messages. Nonverbal behavior is typically unconscious, and therefore the more reliable indicator of a person’s thoughts, feelings, and intentions.
The savvy communicator can spot nonverbal behavior that belies spoken words.
Imagine you work with the man on the left. You approach him with a few ideas, and he tells you, “Great! I’m interested in hearing what you have to say. And I want you to know you can count on me to be open to new ways of doing things.”
If you listened to his words without watching him, you might be greatly encouraged. However, this man is unconsciously displaying extremely defensive nonverbal signals, such as crossed arms and a downturned mouth. His body language is at odds with his polite words. In other words, he is not telling you the truth.