Close circle of friends = Introvert?

[phoenix31]

If someone says that they would rather keep a small circle of close friends that they know well and can trust, as opposed to knowing a lot of people, is that a pretty good indicator that they are an introvert?

 

[BlueScreen]

It's one indicator. Many extroverts do it too though especially as they get older. It just shows a preference for quality over quantity in relationships.