I suppose that you always have to choose only reliable and responsive brokers, otherwise you will fail in trading activity. One can statet hat brokers don't matter in trading activity at all, while I claim that a good broker is almost a 50% of success in your trading activity. In my opinion, traders often state like that because of lack of experience and knowledge. No doubts, that there are some other reasons which affect your successfulness much more than a broker, however broker actually is for your mood and positive attitude, but not for making money. You make money by yourself, you have to remember this.