There is an old insult that states that so-and-so is so unpopular that ‘he couldn’t get elected dog catcher’. The insult is especially nasty because dog catchers are rarely the most popular people in a community and the job itself is generally undesirable.
I work with a number of rescue groups that have a continuing problem. They have dogs that bite people. Sometimes the biting is only a matter of territoriality. The dog goes ballistic when guests come to the house. Sometimes it’s resource guarding. If it is front-door aggression the easy solution is to simply confine the dog when guests arrive.