Such dogs are less of a dog and more of a human creation. Nature would have never created such a dog. It is in nature of canids to avoid fight and danger. Domination rituals, natural aggression and fighting happen under certain circumstances, situations and contexts. Humans should be educated to recognize hints, signals and dog reactions, and, by acting accordingly, avoid it or stop it. However, with dangerous breeds – it is important to emphasize again, due to human unnatural selection – developing dog communication (language) does not happen, so it is difficult to recognize their intentions. And what is more important, such dogs very often get involved in fights because of unnatural urge to fight or hunt. They usually do not use domination rituals to establish hierarchy, but is a trigger to slaughter another specimen.
With dogs that are refined from "breeds", fight will end without serious injuries, very often even without any wound. Dangerous breeds (the list is long) were created to have their boldness before their courage. They defy nature and go beyond limits of proving dominance.
Frequently, they literary slaughter till death. Even when opponent or victim clearly show powerlessness and defeat, their instinct to slaughter will overwhelm them and they will continue to fiercely bite.
If someone points out that such a dog has urge to fight in its blood, and that its owner is allowing it to act in tune with its nature, that owner should be aware that nature did not create such a dog. And that no dangerous breed would exist if humans did not create them. Humans created them. These dogs, as a result of selection, are denied of the aspiration to be stable.