Unfortunately, because the world of dog training is driven by people (trainers) that love dogs most dogs end up being influenced more by their hormones, breed genetics, bloodlines, and evolutionary programs alone, as opposed to these things AND a loving authority figure in the context as is universally found in higher order social species such as dogs, wolves, apes, humans, etc. Here’s how dogs are often led astray, and needlessly become aggressive with unfamiliar dogs. – John Wade