i dont brother what is inside the book, but I want to know what is next after the books, no matter how many books he wrote they are all circulating around the same set of knowledges/insights/thought, the first book is totally identical to the last book, there is barely any context added, if at all, why should people waste too much time to read twice the same textbook? I know some would crave the new book, because it give a brand new experience, new gadget new ux new ui new look new everything, impressive enough to attract new buyer.
New experiences that's your answer there, the new book give a new insight and a brand new understanding of what he was trying to teach in the old books. He has his targeted audience and that's why he's releasing his book in batches. For some people they have to read multiple of his books for them to understand what he was teaching while others have to read just one to get his philosophy. Some publishers spread their writing around different angles of financial education while others focus on just one aspects. You might hate or like him but your can't deny the fact that he has helped alot of people gained financial education that the schools can't teach.
I enjoyed reading his books when I was younger and always look forward to new ones, there mightn't be new things but I understood better what he's was teaching in the previous book. One think I know he explained better was want liability or assets are. He mightn't have more guides after achieving financial freedom but I know when I'll achieved that myself I won't need someone to tell me what next as I would have have already known what next to do to protect my wealth and be able to pass it onto my next generation.