There are ways that a dishonest broker can skim profits off of your trade. One of those ways is by taking advantage of what can be up to a 2 minute gap between the time that you place your order and the time that you see the results on your platform. Second- the broker controls the price you see on your trading platform and there’s a custom made opportunity to shave profit from the transaction if the price moved before the transaction was posted back to your screen.