You can't have lasting, meaningful happiness unless you're willing to continually reinvent yourself. That reinvention must always start with challenging yourself. You essentially kill off the old you and create a new, improved version.
Happiness and prosperity are created by seeking out a continuous progression of escalating challenges—then doing the difficult work of trial, growth, and self-development to overcome them.
This means an exploration of the thoughts you have allowed yourself to be influenced by (whether consciously or subconsciously), the beliefs they caused you to develop, and then what results those beliefs have created.
Radical Rebirth is a wakeup call for anyone who wakes up one day to discover they don't really like (or actually hate) the person they've become. If you're experiencing "divine dissatisfaction" with your life—you're ready to create a new and better version of your life—this is the book you never knew you needed.