There are many concepts that people can learn to improve their success in stock trading. People can learn how to read the market, create a system, be disciplined, and many other principles that can make the trading experience better. Of all those things, there is one that is imperative to long term success when trading stocks. Traders must be able to control their emotions.
You can have a great system, a great stock, a great buy point, you can know what you're doing, you can have paper traded 1,000 times, but when you get into a real trade and money is on the line, if you do not have control of your emotions, poor choices will be made. Fear and greed are two things that can negatively affect your trading.
One way to drastically decrease your emotional responses when trading is to develop a strong support system of people with stock trading knowledge. Having open discussions and building relationships with people who understand this journey helps tremendously with navigating the psychological and emotional aspects of trading stocks.