Dogs that have been mistreated, abandoned, or dumped alongside a road become very loving and loyal family members when they arrive in a good home.
We have a small spayed female mutt of unknown ancestry that my wife rescued as a puppy from a busy street ten or eleven years ago. I didn't want her but she's still here and she's in charge of our daily schedule. She knows what is supposed to occur at every hour of the day and makes sure we don't forget.