In a margin account, the broker uses the $1,000 as a security deposit of sorts. If the investor's position worsens and his or her losses approach $1,000, the broker may initiate a margin call. When this occurs, the broker will usually instruct the investor to either deposit more money into the account or to close out the position to limit the risk to both parties.
The market then wants to trigger one of your pending orders but you may not have enough Forex free margin in your account. That pending order will either not be triggered or will be cancelled automatically. This can cause some traders to think that their broker failed to carry out their orders. Of course in this instance, this just isn't true. It's simply because the trader didn't have enough free margin in their trading account.
In addition, I've had some comments from people suggesting that they'd like to see more varied order types than the simple Market Order. For carrying out proper HFT strategies against OANDA we are going to need to use Limit Orders. This will probably require a reworking of how the system currently executes trades, but it will allow a much bigger universe of trading strategies to be carried out.
If it was this easy to earn money utilising robots, nobody would ever go to work. It is possible that robots can make money for a restricted time period, but they could start losing after awhile - and the money earned by the 'best Forex robot' with one position may disappear before you can claim it. In addition, the vast majority of robots are scalpers. They make just a few pips with every position they take - and they can set a considerably tight target. The chances of surviving with such a strategy are quite limited for a trader.
Back tests – You can read my forex robot reviews to see if the forex robot has back tests which will give you a good idea how it performed historically, some forex robots even back test as for as 15+ years! Ideally, you would want back tests to have been done using real tick data and spreads, thus making the forex robot back test results as accurate as possible in the mt4 strategy tester