You've heard the phrase, "It's all in how you raise them." While there may be some truth buried beneath the connotations of that overused phrase, the real truth is that all dogs are the result of a combination of nature and nurture.
A dog with poor genetics (reference: Otto), a "bad" dog, raised in a good home with good food and a good owner is STILL a "bad" dog.
A dog raised in a bad home with a bad owner (reference: Johnny Justice of the Vick dogs) given a good home and a good owner is a good dog. Had he stayed with Vick, he would have been a "bad" dog.
A dog raised in an environment where she was fed and given shelter, but the owners didn't want to put the effort into training a puppy. Give the right home (one with patience, at least!!), she became a "good dog." (reference: Remi)
Our dogs' behavior is based on a complex combination of genetics and environment. Watch this video shared by PBAM: http://m.youtube.com/watch?v=LDNZZ5nCNGg&desktop_uri=%2Fwatch%3Fv%3DLDNZZ5nCNGg
See how the dog lived? He had an uninvolved owner who was neglectful, at best. Given the right environment, the dog blossomed.
Using the phrase, "It's all in how you raise them" is misleading and lowers the chances for dogs with poor or unknown pasts to get a second chance on life and love. Unless a dog is mentally screwed up (back to those genetics), giving them a chance will prove to be the best thing that ever happened to you...AND the dog!!
Something to think about....