It is human nature...
...to follow what grabs attention. While extroverts are more outspoken and social than introverts they can crave being the center of attention and have trouble with working by themselves. Because of their outspokenness society is generally built to accommodate the extrovert. Whether in the work place, or life in general, humans often want immediate returns to a situation. Extroverts provide that. From this comes the perception it is "undesirable" to not respond fast enough and therefore pressure is applied for the introvert to conform. It is rather one sided.
The value an introvert brings to resolving a question is just as important as that of an extrovert. The introvert will be more likely to incorporate all validated information for an issue, as well as explore the invalid. The results are often displayed in the long run. The balance between the extrovert and the introvert needs to be found. Ms. Cains book is part of the process.
