There are so many reasons behind the loss of the traders in this field , some of the traders don't have enough knowledge but they always take huge risk and do trading without knowledge and experience this things always leads them to see losses which are very huge sometimes they loose their whole capital which is unbearable for any trader. I think main reason of loss is a greed. When we greedy we want more and more profit and become rich in one night so in this condition we can not control our emotions and we loss our all money. Anohter reason of loss is lack of knowledge and experience if we have not much knowledge then also we loss our money. Try to control greed and try to learn more and more about forex.