Are the ones that aren't responsible so thier animal winds up biting someone. Plus many people misread animals body language and don't realize the dog has warned them multiple times they might bite. Or they think "my dog wouldn't hurt anyone" so let the dog run around which can result in an animal doing something they normally wouldn't.

Imo people have heard so much that they have to "dominate" and "show who's boss" to dogs that they train them that way thinking it results in a good, never biting animal when in fact, it has created a ticking time bomb who eventually bites because it's been kicked, jerked, alpha rolled, shocked, or whatnot in order to "dominate" them into being good.