Dear Danny:
I think that the purpose behind the message You Are Enough in self-help books is to create a calm, positive mindset in the reader (if only for a moment), so that the reader will be motivated to improve what he/ she needs to improve.
The alternative message You Are Not Enough, when repeated many times by a parent becomes You Will Never Be Good Enough, and this message demotivates a person to improve, the person gives up.
“If I am a bad father, am I enough? Or can I not aim to improve as a father? Similarly, if I am a bad husband, should I not look to grow and evolve?“- if you are a bad father/ husband/ friend/ neighbor/ employee/ etc., you are not enough and you should improve. But notice: it is I who is saying that another person should improve. How do I motivate another person to want to improve?
By pointing to the part of them that is good-enough so that the person has a good-enough basis to grow and evolve from. I had to find that basis within myself, without which I wouldn’t have been able to grow and evolve in the ways that I have.
anita