The owner of this pet dog was obviously at the end of her tether cleaning up mucky paw prints, and so decided that rather than moan about it, she would do something about it. She purchased a door mat, and then set about trainiing the her pride and joy to use it every time it entered the house from the garden.
Looks like she did an awesome job, perhaps even too good a job, if there is such a thing. Not only does the dog wipe its paws, once, twice three times, the owner has to push the dog inside the house to prevent it from standing there wiping its feet all day long. Well done both of you.