His book is very carefully designed to push you towards buying his other books, then maybe a course or two, then...

It’s always the next book or course that promises actual concrete answers.

It’s not quite at the level of Scientology materials but it’s in the same vein.

It's very consciously engineered to work like that. These books and courses are crass but effective marketing funnels, designed to select those who will continue to pay increasingly improbable sums for access to increasingly "exclusive" information.

Same with other self-help authors, isn‘t it? Take Brian Tracy (not saying he is a charlatan!). Superficially repeating same ideas over and over again, publishing half a dozen books a year with the same ideas.