Not very hard actually. I do financial research for a living and there is a lot of psychology in the science of finance and some of it is related to gambling.
Right now I am analyzing forex traders and 90% of them lose money. I see accounts where people start out with huge sums of money, and lose all of it, typically within a 3 month period. They are not making rational decisions. They are gambling. One specific mechanism is called biased self-attribution. Humans attribute good outcomes to their personal skill (despite skill is not a factor) and attribute bad outcomes to bad luck or other extraneous events.
The key is proper money management. To stop and sit back and find out what one is going wrong. Not many people do that. I always look back and perform an after action review on every trade, and bet, I make to see where I screwed up.
It is difficult making money in the stock market and in gambling. Almost every game is staked against the better and in the long run it is a zero sum game. Very few people, around 5% to 1% (depending on the item being gambled) end out ahead.[/QUOTE
Speaking on gambling, where a line is involved, it is extremely rare to lose 9 out of 10, and to win only 25% over a period of time.