These faults are acquired. They include scars and injuries. These faults are not necessarily desirable or proper. But they are manageable. You can select and manage these faults and still improve the breed.
Defective animals have genetic malformations and diseases.
It makes no sense to attempt to include a defective dog in your breeding program. You can't breed a dog with epilepsy, or a cleft palate or hip dysplasia and expect to improve the breed. Dogs with defects should be spayed, neutered or euthanized, depending on the severity of the defect. A dog with a defect may make a wonderful companion, but it absolutely should not be bred. In the wild, defective animals do not survive, and they do not reproduce.