A person who is experience in reading behavior can pick out what the tail wagging means if it is a happy or a nervous wag. Another example, I met a golden that smiles, the owners say people think it is snarling. People use to think my Watson was growling at them, he was just talking. If they knew how to read dog behavior and body language, they would have known that he was just being a chatter box. Don't get caught up in this one.
All dogs look cute, all dogs are sweet.
However, not all dogs have a good working ethic or stable temperament. I remember over a year ago I was evaluating a dog. He was beautiful. However, he was a scared dog when he was put on tile or brought into the house. The dog had never been off the ranch and never been in a house.