Quiet is, essentially, about introverts in a society built for extroverts. I found the first two thirds of the book enlightening and really interesting. I find myself to be more introverted than extroverted and feel that I was sort of forced into learning some extroversion just to get through in my social life growing up and in school and work. This book captures that struggle in a really insightful way. And I found it a great read/listen when thinking about how our kids are and their personalities.
The author dives into research and anecdotal data about the topics and I really think it's a great framing of this aspect of humanity and how it interweaves with culture, education, work, and more. However, she ends up focusing a lot on Asian culture (Japanese and Chinese, primarily) and the differences between Western and Eastern culture in the area of extroversion/introversion. In many ways she upholds Eastern education and business culture as superior to Western (at least in regards to introversion/extroversion) but, having lived in Japan and worked in education there, I think she failed to discuss the challenges in some of the Eastern culture in these areas. In my opinion it was slightly unfortunate angle but it didn't take away from the core message and value.
If you consider yourself introverted or have a kiddo who isn't an outgoing, rambunctious social dynamo I'd highly recommend this one.