Well, could be one of the reason but certainily not the Major reason why traders fail.
Here is the only reason:
'Trades based on Technical analysis = Gambling, Trades based on Fundamental Analysis = Investing!'
Scalping: minutes to hours
Day trading: hours to days
Swing: days to weeks
Investing: months to years
each trading style will be suitable depending on personnalities. I know traders that scalp the trends (fundamental outlook) based on Technical Analysis, why would they be gamblers?
There can NEVER be JUST ONE REASON why '90%' traders fail bcoz those 90% includes thousands or possibly few million traders around the world. Everyone has different mindset and so does different trading style. A losing factor for few traders may not necessarily be the same losing factor for other traders.
Some lose bcoz of high leverage and at the same time there are traders who win using high leverage bcoz they know how to CORRECTLY and EFFECTIVELY use it. Losing Factorsssss purely differs from trader to trader.
So just wake to the fact that THERE CAN NEVER BE ONE LOSING FACTOR though there can be one major factor.
There are lots of reasons why 90% of traders fail,mostly because they have no formal training ,when your up against the brightest in the industry ,the latests news ,insider knowledge,you can't expect to jump into the ring with mike tyson and not get whacked,unless you know his weakness ,learn his moves inside out,plus someone has to pay for wall street
Fundamentals are skewed and bad news is only released after top managers have sold their own stock,companies lie all the time.
I have a whole list of the things you need to look at first even before fundamentals,examine the board of directors,is there any conflicts of interest,what kind of shares do they have,any more than 9 people on a board is too many,look at SEC filings,court cases,if all that is fine then look at the numbers.
I scalp the eur/usd and I trade stocks.
"They mistook leverage with genius".