The origins of the modern self-help scam date back to 1859, when the very appropriately named Samuel Smiles published a book titled Self-Help. Generally such books supply relatively simple-minded behavioral advice which, it is claimed, if followed will make you a successful and happy person! However, beginning in the early 20th Century, and especially becoming a major social wave in the 1950s, a number of self-help scams arose which actually quickly took the form of very dangerous destructive cults. Scams which do not have a cult structure are often equally dangerous because of their apparent harmlessness (usually coupled with moronic simplicity, which causes them sometimes to be quickly adopted by professionals whose careers are dedicated to improving mental health). Almost every one of the currently-successful self-help cults has a semi-religious basis... meaning that it either imitates the structure of a religion, without being overtly coupled to an existing religion, or that its core teachings are borrowed (sometimes with no credit) from existing cults which are generally very obscure offshoots of Buddhism or Hinduism.  We will discuss only three of these movements: SCIENTOLOGY/DIANETICS (beginning circa 1950, created by pulp-fiction writer L. Ron Hubbard), TRANSCENDENTAL MEDITATION (circa 1960, attributed to Maharishi Mahesh Yogi, but actually synthesized into its "pop" form by some of his followers) and MINDFULNESS (circa 1970, popularized by people like Jon Kabat-Zinn, and largely borrowed piecemeal from a huge number of Eastern religions, but dumbed down to a level of breathtaking vacuousness). The stupifyingly moronic level of Mindfulness as normally presented has made it currently the most overwhelmingly popular of such movements.  It's like the "Full Moon Only" distillation of conventional astrology.   It is also the only such movement that has no aspect of a destructive cult (at least so far). But despite the apparently harmless facade of Mindfulness, it can be quite dangerous in practice. And it is definitely a cult, all the more dangerous for seldom being recognized as such. In general, the religious roots and assumptions of Transcendental Meditation and Mindfulness are often explicitly denied by its promoters, yet in fact the religious origins are explicit and openly admitted by the founders, who at the very same time promote the resulting "technology" as entirely science-based!  And Scientology is explicitly promoted as a new and true religion, which at the same time provides a "technology" to transform its practitioners into god-like super-humans!  Here is the way people looking for self-help advice can wind up in dangerous cults.

L. Ron Hubbard

Maharishi Mahesh Yogi

Jon Kabat-Zinn

But you don't need to found cults to make money in this field. The traditional Samuel Smiles way still also works... just write and publish a best-selling Self-Help book. You need to make the book moronically simplistic, but you also have to have a hook or gimmick that is unique to the book and has a direct appeal to the reader. Writers whose books become best-sellers can usually follow up with up to three new books the very next year, taking advantage of the momentum and publicity created by the first book.  The real problem with the entire self-help scam is that it very deliberately exploits the vulnerabilities of those taken in by the scam. If the victim is already on the verge of genuine mental illness, the self-help advice, not based on any valid clinical or medical understanding, can only do more harm... and push the victim across the border into genuine, crippling problems of mental health. The bottom line is that self-help scams deliberately aim at and exploit the most narrow, selfish and self-absorbed aspects of human personality, and that can never be healthy.

A number of destructive cults promise the customer that if he or she just patiently spends enough money, taking more and more advanced "training," then he or she will ultimately develop god-like supernatural powers, including invisibility at will, immortality, ability to read minds, ability to fly, walk through walls, bring objects into existence out of thin air, etc., etc., etc. Of course, no such "highly evolved" individuals are ever exhibited by the cults.