Genealogists talk about searching friends, associates, and relatives in an attempt to learn where someone came from or find out more about them.
But it’s always possible that someone moved where they did not know anyone. Court records in early 19th century Virginia suggest that an uncle of mine was not thought of kindly by his neighbors and, after some legal troubles, might not have been trusted by his family as well.
After his punishment for his crime was over he headed to what were then the wilds of Missouri to start a new life. Research there located no members of his extended network in Virginia–probably because that was his intent in the first place.