I agree with you. A trader who wants to succeed must first control his emotions and discipline himself. However, most trades are often disciplined and emotional rather than disciplined.
Not all traders are emotional and we see that large number of traders are benefiting here without any difficulty or mistake as they have learned about it. Yes there are traders make emotional decisions which result badly and do not maintain the market discipline and rules that help you handle overall procedure.
Get benefit of trading by controlling your emotions and by following the market rules and principles that will make your way straight towards your destination.