It comes from a wonderful organization called Hope for Paws, whose videos I've come across from time to time. The people involved are borderline saintly, and really know how to be patient and deal with stray and frightened dogs. In this case, they come across a terrified dog, living alone on the streets, and hiding away to protect himself.
Their videos don't generally have The Perfect Ending, because the point of what they post is a way to get people to adopt the animals they've saved and helped adjust to being great pets. But some videos don't need a perfect ending, because what they've got is pretty special all on its own.