Curve fitting sounds like scam

Sellers of bots in the MQL market often engage in practices such as curve fitting and fake backtesting. While some bots may appear to be highly effective during backtesting, particularly those that claim to be AI-based and support multiple currencies, the reality is often quite different. In many cases, it is possible to achieve positive results with as little as a $2 balance, indicating that these sellers may be attempting to deceive their customers. It would be beneficial for MQL5 to investigate these practices, as there is no legitimate reason for sellers to engage in such deception.

someone should  do an article about  curve fitting  and how we can determine    fake  and real  testing

Forum on trading, automated trading systems and testing trading strategies

Tips to avoid being scammed …

Fernando Carreiro, 2022.06.07 14:40

Be it by fake agents, brokers, signals, or EAs, there is one weapon to beat them all — knowledge! Your knowledge is the key to prevent you from being scammed.

Invest and take time to improve your knowledge, to gain experience and improve your skills. Learn to do things for yourself and not to rely on others so much. You don’t have to be a master or even be very good at it, but the more you know and understand, the easier it will be for you to detect when something is not what it seems to be.

Learn how brokers work and how they are licensed and regulated. Learn about the different markets, trading conditions, types of accounts, leverage, and when you don’t understand something, ask first about it and get answers from different sources. Don’t just blindly accept things.

Learn to trade manually, even if you intend to use signals or EAs. You don’t have to be very good at it, but you need to understand all the different concepts of how orders are placed, how they are triggered, how to manage them, how to calculate and manage your risk, and all those pesky little details required to trade manually. Only then can you better evaluate the signals you wish to follow or the EAs you wish to use.

If you are going to hire someone to code your EA for you, then take some time to understand how coding works and some basic knowledge about it. Again, you don’t have to be good at it, but the more you understand, the easier it will be for you to communicate with the developer and provide valid, realistic requirement specifications and to understand how much work is involved as well as its value and how much to budget.

Also, learn to use the Strategy Tester properly and how to interpret the results. The better you understand it, and the more you use it, the easier it will be for you to evaluate the results from EAs you are considering.

So, in conclusion, don’t be a greedy idiot quick to jump onto anything “shiny”. Instead, be wise. Take your time. Invest in your knowledge and skills. Choose carefully.

Hannah Wanjiku Kimari -:
someone should  do an article about  curve fitting  and how we can determine    fake  and real  testing

I found the article (some part of the article) about it (about some way to discover this curve fitting):

How to Test a Trading Robot Before Buying 

Another Symbol/Time Frame

The majority of trading robots are developed so as to trade on one particular symbol and some of them even require to be used on a specific time frame. It appears to be quite reasonable as every instrument behaves in its own way. Therefore, symbol and time frame are, as a rule, always specified in the description of a trading robot offered on MQL5 Market.

Download a demo version of the Expert Advisor and start it on a different symbol and/or period. First, you need to make sure that the Expert Advisor is not going to crash with a critical error or fill the log with trade error messages, being used in inappropriate starting conditions. Second, check that a profitable trading strategy has not become extremely loss-making, due to the above changes in the settings - this can happen where curve fitting had taken place.

One of the easiest ways to arrange that kind of test for the Expert Advisor is to optimize it over all symbols selected in Market Watch. We run the optimization of the Expert Advisor in that mode on a quite long time frame H1 with "Every tick" generation and get a fairly quick answer to the second question.

More -

Curve fitting means that the Expert Advisor will probably not show the same level of profitability on data beyond the specified interval used for the optimization as it did on the test data. And worse yet, it may yield quite the opposite results, leading to losses.

..and more and more about it.
So, it may be good to read the article: How to Test a Trading Robot Before Buying

Optimization Types - Algorithmic Trading, Trading Robots - MetaTrader 5 Help
Two optimization types are available in the tester. You can select the appropriate one on the Settings tab of the Strategy Tester. In this mode...