Most traders and investors are inpatient they only think of the positive side of it ( making profit) not knowing there will always be a loss someday, well most of them know but when they make losses they became frustrated and unstable, some will give up because of that little experience. Sometimes we make losses and we have bad experience like we offend God but no, we are only been tested. Some of the spirit of a trader or invest is "I can make it mindset, resilience...
I read through what you feel that everyone has to know about trading. Your post is in line and understandable. But with respect to your post title, I feel that what you need to know about trading is that TRADING IS NOT FOR EVERYONE.
YES, you read it clear. If you lose and keep losing, quit trading and find some other things to do. Trading is more than profits and losses, it takes patience and emotion to survive in the trading market. If you have tried trading for sometimes and no matter how careful you applied your strategy, you still don't succeed. Please consider to quit trading.