No matter how quiet the neighborhood, all it takes is one car.
Or, your pup could see something interesting and decide to chase it and run far from home.
My boys were trained to stay when I opened the door to the outside. One day my father opened the door and Teddy went shooting out to chase the UPS truck down the street. We were fortunate and I was able to call him to me and he obeyed. However, there are many stories here of less fortunate people.
Be careful if you use any type of tie up outdoors. Always use a harness and supervise closely. It is very easy for these guys to get the tie (chain or otherwise) wrapped around a fragile leg or neck. Never leave him unattended because he would vulnerable to loose dogs, predatory birds (my neighbor's Yorkie was attacked by a hawk last week and is lucky to be alive).
Sorry for all the scare stories, but the fact is little dogs are vulnerable.