One of the kindest things any person can do is to adopt an animal from a shelter or humane society. These are animals that desperately need a home and human beings to love and care for them. However, if you have decided to adopt a dog from a rescue situation, you must go in with your eyes wide open.
For the health and wellbeing of your dog, training should really not ever be considered an option when owning a dog. Well trained dogs are more likely to be behaved and listen, be void of behavioral issues, be good in public, and are less likely to bite. Owners also have a much closer connection with the dog when the time is taken to form a relationship through training.
If you ever owned a dog when you were a child, you can probably recall the joy and exhilaration you felt every day, playing with your best buddy. Once you grew up and (assuming you) started a family, you probably wanted your kid(s) to experience the same things that you did. A loving, loyal, fun-loving animal companion is one of the best things in the world.