The problem with most self-help literature is that there is no widely accepted understanding of what the self is, which can be a bit of a problem if the goal is to develop new and better you.
"The Self in Self-Help" says it better.
If, like me, you have read your way through sober Stephen R. Covey (The 7 Habits of Highly Effective People) and godly Norman Vincent Peale (The Power of Positive Thinking), through exuberant Tony Robbins (Unleash the Power Within) and ridiculous Rhonda Byrne (The Secret), through John Gray who Is From Mars and Timothy Ferriss who has a four-hour everything and Deepak Chopra who at this point really is one with the universe (65 books and counting)—anyway, if you, too, have reckoned with the size and scope of the self-help movement, you probably share my initial intuition about what it has to say about the self: lots. It turns out, though, that all that surface noise is deceptive. Underneath what appears to be umptebajillion ideas about who we are and how we work, the self-help movement has a startling paucity of theories about the self. To be precise: It has one.
Let us call it the master theory of self-help. It goes like this: Somewhere below or above or beyond the part of you that is struggling with weight loss or procrastination or whatever your particular problem might be, there is another part of you that is immune to that problem and capable of solving it for the rest of you....
But, in the spirit of being a better person, I should not be so hard on self-help. The fact is, selves are profoundly difficult to understand. 'There is nothing that we know more intimately than conscious experience,' the contemporary philosopher David Chalmers observes, 'but there is nothing that is harder to explain.'
It's remarkable to me that the experience of self is at once the most intimate one we'll ever have, and yet simultaneously almost impossibly opaque.
The rest of the piece is well worth a read if you have time.