"Internet marketing" is full of this.
Folks start out trying to make money online, until the eventually come to realise, the only way to make money online, is to sell a product telling other people how to make money online.
Folks start out trying to make money online, until the eventually come to realise, the only way to make money online, is to sell a product telling other people how to make money online.
That's patently untrue. For every huckster hawking his latest course, there are 10x as many successful marketers. You just never hear about them because they run actually successful websites.
Anyone you see ranking for "best hosting" or "best website builder" is likely pulling in nearly 6 figures a month
I suppose this is not limited to the internet marketing genre, but I've found from my own experience, this is common.
Small anecdote: I was once asked to review an ebook in the internet marketing space based on some things I was doing at the time. The "author" had created an ebook that consisted of clipart, default Microsoft Word formatting, and egregious spacing to pump up the page count. The "author" was furious when my review was neutral rather than glowing.