Greed and fear are a recipe for disaster in trading. Those kinds of emotions can bring about huge losses.
The key to success as you say is to accept that some trades just won't go in your favour. That's why it's important to trade without emotions, and to look to make small, consistent profits. That way, if and when things go wrong, you're not putting yourself in a terrible position.
agree with you
Greed is honestly probably the number one thing that will hurt you. I have been up a very nice amount and not taken profits from the trade. The reason is greed, you start seeing dollar signs and think your investment is going to keep going.