It's a natural instinct that releases endorphins in their brain.
Puppies learn to lick from their mothers, who use it for cleaning and stimulation. They continue this behavior to show affection and comfort themselves and their littermates.
Dogs lick to enhance their sense of smell. They often enjoy licking areas of our bodies that have strong tastes and smells, such as our hands, faces, ears, and feet.
Dogs lick hands to investigate the smells and flavors collected throughout the day. The salty residue left by sweat on your palms is also appealing to them.
Dogs lick faces for the attractive smells and tastes they offer. Licking faces is also an instinctual behavior for dogs, used for mutual grooming, affection, and communication.
Dogs may lick ears to taste them, keep them clean, or show extra love. The apocrine glands in your ear canals secrete a fluid that creates an enticing odor for dogs.
Excessive licking can indicate boredom, anxiety, or a medical issue. If your dog's licking behavior seems problematic, it's recommended to seek help from a professional.