Overall, this an enlightening book-- the in-fighting, the drama, the comments made by people who had worked under Trump for awhile that foreshadow the toxic environment... overall, you see that incompetence of Trump's cabinet members was not the main culprit in them being "fired". Rather, Bolton paints a picture: any view that challenged Trump's did not result in debate and introspection, but animus and hostility. Most of Trump's decisions were not meant to shake things up, Bolton attempts to convey. Rather, they were impulsive, misinformed, and at worst, detrimental to the security of the US and its almost century-long allies.
John Bolton is not an author. He is a National Security Advisor. Therefore, his writing is dry, and a shrewd editor could have helped with brevity. On the other hand, the book is thorough— extremely thorough. That being said, it's also a book meant to be consumed by the general public. A little color would have been welcome and could have helped to get through some of the more banal segments of the book.
If you want Thoreau's poetic musings, it's not for you. If you are expecting a children's book with pictures, it's not for you. If you expect a conservative memoire to NOT include vast amounts of conservative/hawkish policy opinion, it's not for you.
However, if you would like to peer behind the curtain, and see what led to one of the highest White House staff turnover rates in history, pick it up. You will see that, political opinions aside, Trump was wholly incapable of delegating and listening to individuals vastly more experienced in the nuances of running parts of government.