Have you read the book? It is highly recommended. The book by Dr. Henry Cloud tells us to live a healthier balanced life by having boundaries that become personal property lines that mark who we are and who we are not by knowing when to say yes or say no.
Having boundaries can also lead to comfort, complacency, and lack of ambition. They can become walls that limit or inhibit growth, opportunity or reaching greater potential.
Be cautious with your boundaries. Recognize that some of them can, will and must change at times just as your age and goals change over time.
Have boundaries. But make sure you control them, not the other way around.