“In the first study, Grant and his colleagues analyzed data from one of the five biggest pizza chains in the United States. They discovered that the weekly profits of the stores managed by extroverts were 16 percent higher than the profits of those led by introverts—but only when the employees were passive types who tended to do their job without exercising initiative. Introverted leaders had the exact opposite results. When they worked with employees who actively tried to improve work procedures, their stores outperformed those led by extroverts by more than 14 percent.”

“Introverts need to trust their gut and share their ideas as powerfully as they can. This does not mean aping extroverts; ideas can be shared quietly, they can be communicated in writing, they can be packaged into highly produced lectures, they can be advanced by allies. The trick for introverts is to honor their own styles instead of allowing themselves to be swept up by prevailing norms.”

“Introverts, in contrast, may have strong social skills and enjoy parties and business meetings, but after a while wish they were home in their pajamas. They prefer to devote their social energies to close friends, colleagues, and family. They listen more than they talk, think before they speak, and often feel as if they express themselves better in writing than in conversation. They tend to dislike conflict. Many have a horror of small talk, but enjoy deep discussions.”

“One noteworthy study suggests that people who suppress negative emotions tend to leak those emotions later in unexpected ways. The psychologist Judith Grob asked people to hide their emotions when she showed them disgusting images. She even had them hold pens in their mouths to prevent them from frowning. She found that this group reported feeling less disgusted by the pictures than did those who'd been allowed to react naturally. Later, however, the people who hid their emotions suffered side effects. Their memory was impaired, and the negative emotions they'd suppressed seemed to color their outlook. When Grob had them fill in the missing letter to the word "gr_ss", for example, they were more likely than others to offer "gross" rather than "grass". "People who tend to [suppress their negative emotions] regularly," concludes Grob, "might start to see their world in a more negative light." p. 223”

“Indeed, your biggest challenge may be to fully harness your strengths. You may be so busy trying to appear like a zestful, reward-sensitive extrovert that you undervalue your own talents, or feel underestimated by those around you. But when you’re focused on a project that you care about, you probably find that your energy is boundless.”

“Introversion- along with its cousins sensitivity, seriousness, and shyness- is now a second-class personality trait, somewhere between a disappointment and a pathology. Introverts living in the Extrovert Ideal are like women in a man's world, discounted because of a trait that goes to the core of who they are. Extroversion is an enormously appealing personality style, but we've turned it into an oppressive standard to which most of us feel we must conform.”

“Persistence isn't very glamorous. If genius is one percent inspiration and ninety-nine percent perspiration, then as a culture we tend to lionize the one percent. We love its flash and dazzle. But great power lies in the other ninety-nine percent.”