The internet is not a place for you to self-diagnose and treat your pet. I saw way too many things happen to pets that didn’t need to. Like putting oregano or oil in your dog’s ear to treat an ear infection.
It’s not cute to have a dog that obsessively protects you. It means they see you as a resource to guard. Nothing more than a toy or bone. They are supposed to belong to you, not the other way around
Getting and relying on medical advice from breeders and groomers (with no medical background). I once saw a rat terrier with a fractured humerus, which typically requires surgical correction. As I stepped out of the room to check availability with a surgeon, the client called the dog’s breeder who said not to follow my advice and to “just put the dog in a sling” and that she’s “done on her own dog’s plenty.”
Also, not exercising dogs enough. Many behavioral problems can be solved with ample exercise daily.