Most animals love their owners. It's how they react to folks entering the home, or outside.. that is the issue.. We had an Anatolian Shepherd once.. it bit someone--outside. That dog was sent to a farm immediately. And she was the sweetest little thing to my wife and I...
My Mini-schnauzer chewed my brother up last week (the brother who most deserved it too, but that's another story ;) ).
He came in my house and he grabbed her when she started barking at him. He's miffed with me (for the b'zillionth time), I apologized...but bottom line is she did what I wanted her to do with any intruder.