Some people are compared to dogs in bad ways. People who are unkind or uncaring can be described as “ meaner than a junkyard dog. ” Junkyard dogs live in places where people throw away things they do not want. Mean dogs are often used to guard this property. They bark at or attack people who try to enter the property. However , sometimes a person who appears to be mean and threatening is really not so bad , so we also say , “ His bark is worse than his bite. ”