I am sorry to say this! majority if not all signal providers at MQL5 are using a strategy with a small TP,huge SL or no SL at all with combination of martingale, in the short term perspective equity curve to this kind of strategies may look very smooth and attractive, with very high winning rate of course it is expected with 10 or 15 pips TP it is very achievable, but you cannot beat the market all the time and the moment it starts to go against your trade your trading capital is doomed especially if you dont have huge capital to cover your draw down and even if you have a huge capital to spend it is still a very risky thing to do. But still there are a lot of subscribers buy to such signal because of the nice equity curve, but when reality strike to this signals you will start to realize that these traders are not actually trading but they are gambling with style.
It is important for subscribers to realize that stable and safe strategies are those that implement stop loss, with good risk reward ratio(at least 1:1) and never use martingale approach, the winning rate may not be as good as those with top signal providers but you are sure that your investment are safe and will last for years. But the thing is majority of subscribers always look for nice equity curve without thoroughly evaluating the strategy of a particular signal provider or they may know it but they just pretend not to know because they want quick profits in their trading account and they hope that they can reap profits before their equity gets wiped out.
Good article here: