Can signal providers give false trading history?

 
I am about to start following a few signals however when I go to the reviews section I see people complaining about how they are getting losses when the signal providers are showing profits? Why is this? Also if a signal provider has 9 months worth of results showing does that mean that they are true and verified results? If so who verifies them and how are they verified. Does this mean that they been activly trading on mql5 for those 9 months? How could the results be manipulated? Anyone know/ Cheers
 
For the first question, I think the problem is more common when you are subscribed to a scalper. These people would be entering the market and then get out of the market in the next minute, only after a few pips. Because there is a lag time (slippage) between the time when they enter a trade and the time it is copied to your account, your account will be getting into the trade just about the time the provider is about to close his at profits. Because of spread, usually when you get into the trade you get in at a loss. So at this point if the scalper is closing his trade then the same will happen to your account, which then closes at a loss even thought they made a profit. I think that when MQL5 comments on a trading signal that "too frequent deals may negatively impact on copying results" this is what they mean. 
 
Kevozz:
For the first question, I think the problem is more common when you are subscribed to a scalper. These people would be entering the market and then get out of the market in the next minute, only after a few pips. Because there is a lag time (slippage) between the time when they enter a trade and the time it is copied to your account, your account will be getting into the trade just about the time the provider is about to close his at profits. Because of spread, usually when you get into the trade you get in at a loss. So at this point if the scalper is closing his trade then the same will happen to your account, which then closes at a loss even thought they made a profit. I think that when MQL5 comments on a trading signal that "too frequent deals may negatively impact on copying results" this is what they mean. 
very clear explanation.
 
Kevozz:
For the first question, I think the problem is more common when you are subscribed to a scalper. These people would be entering the market and then get out of the market in the next minute, only after a few pips. Because there is a lag time (slippage) between the time when they enter a trade and the time it is copied to your account, your account will be getting into the trade just about the time the provider is about to close his at profits. Because of spread, usually when you get into the trade you get in at a loss. So at this point if the scalper is closing his trade then the same will happen to your account, which then closes at a loss even thought they made a profit. I think that when MQL5 comments on a trading signal that "too frequent deals may negatively impact on copying results" this is what they mean. 

Thanks mate

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