Why does people keep saying that trading psychology matters the most?

<p id="isPasted">There are three steps to create a profitable trading system:</p><ul><li>Strategy</li><li>Process</li><li>Trading Psychology</li></ul><p>For a beginner, Trading is 100% skill. He will need to focus 100% of his time on developing his skill only.</p><p>Trading Psychology is the last step in trading system. New traders should not worry about psychology. First step is choose your style, then select your trading timeframe and then choose a strategy within that trading timeframe.</p><p>The next step is create a process around that strategy. Like entry, stop loss, Position Sizing and Risk Management, Exits, Risk and Reward of system etc.</p><p>Once you have a strategy and system which you have successfully backtested and also traded it in live market. You should have gained enough confidence in your system.</p><p>Now only trading psychology comes into play. Once you have a profitable system which is extensively backtested and traded in live market also. But still if you are struggling with this profitable system. The main reason for this problem will be Trading Psychology.</p><p>Now trading becomes 80% psychology and 20% skill.</p><p>Trader Psychology problems. The two main emotions which drives us are Fear and Greed. Other trader psychology issues are overconfidence, Loss aversion, Confirmation bias, FOMO Regret etc. Now only we need to try to find hacks to tackle the psychology issues which we are facing</p><p>Every trader will have different psychology problems.</p>