Answer by Dave Hughe:
The truth is: you never know. But there is definitely a conflict of interest between the client and the broker regardless of what they say.
Always assume that your broker might be trading against you and question everything that happens in your account. Prior to committing to any broker check all reviews and opinions that you can find on that broker on the Internet.
On the other hand, do not go to extremes and blame your broker for your own mistakes. Try to look at each situation from both sides.