From my experience, here are 4 reasons I discovered:
Valid reasons you have put across, but I think even if a trader developed these attributes many show signs of greed and emotions disguised as gambling because they want to be overnight millionaires which never happens unless once in a million trades...
1/ Lack of Discipline— a) Not sticking to one strategy, b) not respecting your trading rules, c) not sticking to your plan.
Having being on the trading table before, I can tell you that it's difficult to develop this skill because price doesn't immediately go into profits once your trade is triggered, and nobody wants to be in losing position hence the indiscipline.
2/ Lack of knowledge—Inadequate understanding of the market, trading strategy, financial instruments, and fundamentals can lead to poor decision-making.
Having the knowledge should be priority one for one to develop a trading plan.
3/ Not having a mechanical trading system—This leads to emotional trading. Decisions driven by emotions like fear and greed rather than rational analysis result in significant losses.
Guess this comes with the knowledge you talked of above
![Wink](https://bitcointalk.org/Smileys/default/wink.gif)
4/ Overtrading—Taking many trades will affect your decision-making ability and lead to poor decisions.
If there are other reasons why traders lose money, share them with me.
The stats are there for all to see and profitable traders take a 2-3 trades in a month sometimes the motive is to make a 1% ROI and wait for next setup which is good for one's mental health.