The final fatal flaw to overcome as a trader is a Lack of Money Management, and this topic deserves more than just a few paragraphs, because money management encompasses risk/reward analysis, probability of success and failure, protective stops and so much more. Even so, I would like to address the subject of money management with a focus on risk as a function of portfolio size.
Now the big boys (i.e., the professional traders) tend to limit their risk on any given position to 1% - 3% of their portfolio. If we apply this rule to ourselves, then for every $5,000 we have in our trading account, we can risk only $50 - $150 on any given trade. Stocks might be a little different, but a $50 stop in Corn, which is one point, is simply too tight a stop, especially when the 10-day average trading range in Corn recently has been more than 10 points. A more plausible stop might be five points or 10, in which case, depending on what percentage of your total portfolio you want to risk, you would need an account size between $15,000 and $50,000.
Simply put, I believe that many traders begin to trade either under-funded or without sufficient capital in their trading account to trade the markets they choose to trade. And that doesn't even address the size that they trade (i.e., multiple contracts).
To overcome this fatal flaw, let me expand on the logic from the "aim small, miss small" movie line. If you have a small trading account, then trade small. You can accomplish this by trading fewer contracts, or trading e-mini contracts or even stocks. Bottom line, on your way to becoming a consistently successful trader, you must realize that one key is longevity. If your risk on any given position is relatively small, then you can weather the rough spots. Conversely, if you risk 25% of your portfolio on each trade, after four consecutive losers, you're out all together.