 In addition, a small dog has better maneuverability and can more easily avoid being bitten.Because of this, small dogs often receive less injury underground than larger dogs, which are more likely to find themselves jammed in a den pipe, face to face with the quarry, and unable to move forward or backward.Other important requirements of a working terrier are an essential gameness, a good nose, and an ability to problem solve in order to avoid coming to harm underground.