You as a retail forex trader need to understand that forex brokers are in the end above all marketing machines. Since more than 90% of the new traders dont survive long and give up trading after losing their hard earned money, forex brokers need a constant flow of new clients.
To entice new traders, vast sums of money are spent on advertising. Just Google, any keyword related to forex and you will find so many ads by forex brokers giving you so many incentives to start trading forex.
Forex brokers want you to trade more. They use many methods as incentives to make you do that. One of the methods is to hold a Forex Trading Contest by announcing cash prizes of $2000, $1000 and $500 for the top three.
In order to win, many small traders get wiped out losing their money. This is just a trick forex brokers use to make you trade more. The more you trade, the more money your broker makes. This trick is similar to a lottery.
There is no check on the forex brokers. They can quote any rate to you. Forex brokers do this by adding 2 3 or even more pips to the interbank market pip spread
Just imagine by acting only as middlemen between the interbank market and retail forex trader, forex brokers make risk free profits of 3 to 4 pips on a round trip trade.
There is a practice used by forex brokers called Price Shading. For example, if the broker is convinced that Euro is on an uptrend and its price is going to rise, the broker will shade his price quote slightly higher to take advantage of the likely increase in Euro price.
If the broker sees that many traders have placed stop orders at a certain price level, he will mount a sudden attack to take out all the stop order by momentarily spiking his price feed.
You cant do anything. It was a momentary spike, so small that it only tripped the stop losses.
Since, there is no central exchange to compare moment by moment prices, your broker can offer any excuse like there was sudden large order in the market or the broker feed is much faster and reflects true interbank rates.