Trading is a risk business. Writing books is a chance business. You can lose money by trading, but not by writing. So it’s a little like diversification.
There are secrets, tho. It depends on the people and their beliefs. Take a simple example: You walk to the local supermarket and see a bargain price of 20 cents per 2 litre coke bottle. What will you do? Some may tell it their friends and they will also join the line and buy the bottles. Some may keep it as secret and try to buy it all one after another. They fear if they tell it that all the friends buy the bottles and price will go up. Which is completely sound. Plus which will happen anyways, because if you have a bunch of hundred people, some don’t think that far and tell it to their friends, at least to brag.
What happens in the end? This bargain shopping will come to an end one way or another. The early birds get the best price and the late comers will find no bottles anymore. Now if that with the bargain events happens regularly some may write books about it or tell it at the web. Demand rises and what happens if demand rises? Price goes up! What was a former great deal becomes a boring one.
So, that was an example, but it is the same imo in the trading business. The best thing you can do to make money is to hide it if you find something special. Don’t think it will be hidden for eternity, tho. Some may find the same thing and talk or write about it. Plus if somebody already got rich and his methods lose power he might become interested in bragging, too, and even more money if he comes up with his trading “secrets” in a book.
Or take another example: You find a new invention. For instance a rectangle wheel for cars. If you are the first inventor, you may try to get a patent. Or/and to keep it secret. So, when will the time start to have books written about rectangle wheels? If there is already a patent or if everybody drives with rectangle wheels! Which manufacturer earned probably the most money? Those who manufactured rectangle wheels the first time! The late comers may still make money with it, but it get’s harder.
Bottom line: Markets are everywhere. There is even a market for trading strategies. What will we find in those market? A lot of intermediate strategies, a lot of losers and a very few brilliant strategies which are typically either expensive or not revealed til they lose their edge!
The best books are imo not those who give you a detailed strat, but those where you can learn to assemble your own strategies! I’ve read hundreds of books and what I can say 95% of all books don’t even reveal why a strat should work. If I read a book and they tell something about a strat and can’t explain why it works, why would I trade such a black box with old charts and some good looking trades of the past? In hindsight it’s easy, isn’t it?
Same thing goes for robots. Why would I buy a black box everybody can buy? If it’s good, everybody trades with it til the edge is no edge anymore. While most anyways have no edge from the beginning. Ridiculous how many give you a pay back warranty for some days, lol. If a bot trades for peanut profits of a few pips just to lose it in a big loss after some months you can bet there is not even an edge! This is just bait and switch. It doesn’t even need trading knowledge to create a bot which has hundreds of winners one after another in some months to make it looking good for the buyer, just to lose it all in a few big losers afterwards!
So, take it all with a grain of salt what is written or produced in this business!