It does describe a few of axes of your personality, but it's not that great. It's not like they are really poles - you don't get many total introverts or extroverts, people sit on a continuum. A normally distributed attribute is a lousy way to categorize people.
Introverts are people who tend to think before acting (which makes them more shy), and extroverts act before thinking (which makes them less shy), but those aren't the only factors in social adeptness. A polite introvert who can make good jokes will have more friends than the extroverted class bully.
The main value of MB is that it's value free. It's easy to talk about introversion-extroversion, sensing-intuition, thinking-feeling or judging-perceiving; it's hard to say people are lazy-hardworking, boring-interesting, smart-dumb, or brave-cowardly.
Introverts are people who tend to think before acting (which makes them more shy), and extroverts act before thinking (which makes them less shy), but those aren't the only factors in social adeptness. A polite introvert who can make good jokes will have more friends than the extroverted class bully.
The main value of MB is that it's value free. It's easy to talk about introversion-extroversion, sensing-intuition, thinking-feeling or judging-perceiving; it's hard to say people are lazy-hardworking, boring-interesting, smart-dumb, or brave-cowardly.