A Dog Shock Collar is the most common tool used when training dogs. Inexpensive, safe, and effective, this clever device is able to give guidance to what behaviors are right and wrong. They come in different sizes; so rest assure that even your smallest pet can have a collar that will fit properly and will deliver significantly less static than those used on larger dogs. Shock Collars are customizable; you'll be able to select the level of static based upon the persistence and attitude of the pet.
Dog shock collars are cruel and barbaric
Positive reinforcing is more effective, and proven to be a safe way to train dogs.
Why do you say so?
Really? And why do some people still prefer to use them?

That's in a sense barbaric using shock collars just use treats, a dog gps tracker, a leash and a positive attitude.