Of equal importance were the specific differences that he cited along with the examination of whether or not leaders were made or born. This is not the classical trait theory approach but is well reasoned and balanced. Lastly, Kotter specifies the type of scenarios which call for leadership competencies.
I recommend this book highly for anyone wanting to understand how leadership truly differs from management and how the two functions interrelate. Other leadership books seem to emphasize examples of great leaders without the research, balance, or depth of Kotter.
How he has gotten the world to swallow this nonsense book after book, each one a rehash of his previous mishmash of meaningless business speak ("energizing your employees") and vague, unfollowable axioms about, for example, "having vision," is beyond me. But perhaps I just haven't achieved my full alignment potential.
Honestly, seeing this book up on the shelves of seemingly intelligent business people baffles me. Especially since it sits next to works by other self-help authors who dish out the same insubstantial pap book after book. And keep landing on the bestseller list! If you really want to learn how to be a highly effective person, spend some time playing with your children. Bring your spouse some flowers. Read a worthwhile book. Now those are platitudes worth living by.
Another great, easy-to-read, and popular leadership book my company uses successfully for management development and training is strongly recommended: "The Leader's Guide: 15 Essential Skills."