Personality

Extrovert or introvert, it's a Personality thing that you're mostly born into; it's not a Character thing.   In Quiet: The Power of Introverts in a World That Can't Stop Talking, author Susan Cain says that American culture transformed from a Culture of Character to a Culture of Personality early last century.

Character refers to high standards that anyone can choose to live up to:  diligence, honesty, duty, loyalty, compassion, these are character qualities.  Personality is more limited to what your genes give you:  whether you prefer to talk or think, whether you like loud or quiet environments, your natural ability to tell jokes (or your total lack of said ability), these are personality traits.

The kind of personality that made it big in 20th century America was the extrovert.  Author Cain traces the developing trend in books:  Masterful Personality in 1910, How to Win Friends and Influence People 1936, Organization Man 1956.  The ideal became the extrovert who dominates, charms, talks the most, entertains, and usually gets his/her way.

Introverts can feel they don't have much to offer in comparison.  For a classic story told from an introvert's point of view, read Rebecca through to the end and enjoy her paradigm shift.