Don't think of operant conditioning as a "training method" or something we "do to the dog".
Think of it like gravity. It just is. It's a phenomenon ... a law of nature that exists in the environment and is a reason we learn to do or not do something.
A dog in the wild will learn to "operate" his environment to fulfill his needs, in accordance with the consequences of his actions. When we take that dog in and train him, all we do is control the consequences.