Some dogs might engage in excessive licking as a self-soothing behavior, especially if they're feeling uncomfortable or uncertain. Skin conditions, allergies, pain, discomfort, or infections could lead to excessive licking as the dog tries to alleviate the discomfort. Dogs might lick surfaces or objects due to the taste or smell of something on those surfaces. If your dog's excessive licking behavior is persistent, frequent, or seems to be causing distress, it's recommended to consult with a veterinarian.