Every organism with a brain, (from a fish to a human and every animal with in between) operates under the same behavioral laws of learning. A sparrow might not find a bone as enjoyable or motivating as a dog would. He would prefer some bird seed. A fish wouldn't like being scratched behind the ears. He'd rather swim freely in clean water.
Every dog operates under the laws of learning. Reinforcement for a behavior greatly increases the odds of that behavior reoccurring.
Lack of reinforcement or no pay-off decreases the occurrence of a particular behavior in the future. Punishment also can stop a behavior. But punishment, especially harsh punishment carries with it some serious and detrimental baggage in training dogs and runs a great risk of causing aggression. This has been a major source of my training & behavior consulting business. Lots of Cesar Milan followers found themselves in trouble.
A lot of people don't keep their mind on what they're doing. Count the number of times a day your dog gets reinforced for a behavior you don't like. Maybe he doesn't get reinforced by you...maybe all by himself. Or something in the environment gives him a pay-off. Maybe the behavior itself is enjoyable and he's permitted to engage in it, even for a short time. And by the time you notice, he's already been reinforced for it a number of times. It's a full time job to stay on top of every little thing. Just reinforcing one or two behaviors out of a whole day's worth isn't going to guarantee flawless behavior. So take the average dog owner who is even less on top of it than we are, who doesn't have a clue about behavior and training, it's amazing how well most dogs turn out anyway. But those who rely on punishment; threats, scare tactics, harsh voices, pain are opening their dogs up for a lot of potential problems and not a very good bond. A lot of people too, only notice rotten behavior and punish it without giving an alternative and rewarding behavior choice. My dogs might do a few things I don't like, but their day is also filled with and I emphasize reinforcing behaviors, so they tend to do those more which squeezes out the time remaining for unwanted behaviors. A lot of people don't do this and think positive reinforcement training is ignoring unwanted behaviors, bribing with cookies, letting their dog do what it wants. That's IGNORANCE for you...Pure, unadulterated ignorance.
Learning to set a dog's environment up so he's less apt to fail (thus inexperienced owner/trainer feels a need to punish) prevents failure and increases success for which more reinforcement can be added. Preventing unwanted behavior in the first place lessens the chance of the dog being reinforced for it and the behavior will not develop. Or...if it's just in it's infancy, being unable to practice it and be reinforced for it anymore....will cause the behavior to extinguish. Replacing or displacing unwanted behavior with
incompatible and desired behaviors will fill the dog's repertoire (or gas tank, if you will) with wanted behaviors. The fuller the "gas tank" is with reinforcement for wanted behavior, the less room there is for unwanted behaviors.
Scoldings, forcefulness, intimidation, threats, coercion, physical discomfort runs great risk of eroding the relationship between owner and dog, creating a dog who lacks confidence and therefore raising the odds of fearfulness and distrust. Obviously those things aren't compatible with a rock solid, trustworthy and safe animal. It also creates a situation where the dog behaves well in the presence of the owner because it's unsafe to do otherwise. And increases the likelihood of the dog misbehaving in the absence of the owner....because it is safe. Dogs, in fact all living creatures do things because they're safe and don't do things because they're dangerous. Dogs are amoral. So, they're not doing the no no because they're sneaky and conniving and rationalizing it all out. They do things because it works. Period. They're animals.
If they can train wild animals, which they do in zoos and wild life farms where they have to be able to handle them for veterinary reasons and moving them etc, with clicker training, without punishment (It's pretty hard to punish a large sea animal at Sea World) you must know that you can train the most biddable domestic animal, the dog, designed by nature to work with humans without intimidation, physical punishment, force and so forth. In fact, it's done ALL THE TIME.
No, not every dog has the same set of motivators exactly or the same drives. But every dog can be trained using proper and correct methods without the use of pain, threats, intimidation, scary things. I have trained a lot of dogs and all I ever really need is adding the good thing, preventing or removing the good thing, removing a bad thing that's already happening naturally in the environment. But I don't need to add a bad thing.
Every dog works the same way. Different motivators, different temperaments, various degrees of distraction toward things, various drives.... so naturally there are some variations with the details. But the basics, the concepts and laws of learning work the same way on
all animals. It is up to the owner or trainer to discover the dog's motivations, what excites him, what he doesn't like, his fears, at what distance is he fearful of something and a whole lot more. But the laws of learning behavior are like the laws of physics. Gravity causes an apple to fall from the tree. Consequences... or lack thereof....cause and effect....creates or extinguishes a behavior in all living organisms with a brain.
So yeah...I get weary of people saying positive reinforcement training methods don't work on "all" dogs. If they follow the laws of learning, they do. You wouldn't say the laws of physics, gravity in particular doesn't apply to one kind of apple, but not the other, would you?