Your best friends are bad at getting you a job

In 1973, sociologist Mark Granovetter tracked how people in a Massachusetts town had actually found their current jobs, and the pattern ran against the obvious guess. It wasn't close family and best friends who supplied the leads that mattered most. It was acquaintances — former coworkers, a neighbor's cousin, someone from a class two years ago — people connected loosely enough that Granovetter called the relationship a "weak tie."

The reason is almost mechanical. Your close friends mostly know the same people you know, read the same feeds, hear about the same openings — their information overlaps with yours. An acquaintance sits in a different social cluster entirely, with a completely different set of things they've heard. Granovetter's argument, since cited tens of thousands of times, is that weak ties function as bridges between otherwise disconnected pockets of a social network, and information can only travel long distances across bridges. Strong ties just recirculate what's already local.

It's a strange kind of intimacy math: the people who love you most are, structurally, the worst positioned to widen your world.

The person who changes your life is often someone you'd struggle to describe as a friend at all.