That is not a meaningful thing because when someone has the ability and expertise he has the opportunity to be able to make a profit. In the world of trading everything depends on the capabilities and experience that we have, when we are able to make good decisions and choose the right investment, we will make a profit and even achieve success.
Also sometimes luck will bring good addition to your success, you'll be able to generate much higher profits when your luck showed up in the right timing, it's hard to gain if you are not that familiar enough but when you already have a good skills then you'll find good benefits with this market.