Introverts are good writers because they've been refining their inner dialogue their whole lives and have imaginary conversations with people on a daily basis.
Writer: *Writes for hours*
Writer: I just wrote SO MANY WORDS! 100,000? 200,000? A MILLION!!!??? No, I should be realistic. I bet it's 10,000
Word count: 250
Writer: *Screams internally*
I have some sad news to tell you all today.
Apparently daydreaming about your story does not, in fact, make your story spontaneously appear fully written in your word document.