1) B.S. Backtesting.
Why is it B.S you ask? Because as Michal told me - "Edward you must KNOW what you are doing". And most people haven't the foggiest idea of what they are doing when it comes to trading or programming let alone both. Too many good ideas are annihilated by stupid principals. Do you really think that Avery and other savvy traders are taking all market orders for a scalping system? Do you really think that I don't know what the market is doing within a 1 minute bar? Or that I care what the S&P was doing in 1997 (the market has changed in several big ways since then)? Or other such rubbish? Get real. 99% of all aspiring traders are not smart enough to effectively backtest their ideas because they can't trade in the first place

2) No money = no money.
This is a simple but really prevalent problem. I just talked with a trader two weeks ago. He could not understand why he has blown out 2 $5k accounts trading the Russell - and he was trading 2 contracts! I told him that even with my best system I would not trade 1 contract on the Russell with less than $5k. Got that? You need money - at least $15-25k and then only if you can trade will that do you any good.
3) Heard about the "X" indicator.
This is the Jesse Livermore principal. When I first read Reminiscences I thought Jesse was an ass for listening to all those turkey tips. But it's more true than ever today. Instead of "tips" these days its indicators. Buddy I got a new indicator for you - it's called the "Big Money" indicator. What does it do? I have no idea - but it will make you a fortune. Only $599.99. You want to know my secret indicator? It's called the BuyZone - it's a classic breakout indicator. Been around for at least 50 years. I also use another arcane indicator - it's called a moving average :0. That's all you need! The rest is all about your trading competence. As Jesse says - only the market can tell you about the market. Indicators are only a guideline - the operator is one who can discern true market action.
4) No Discipline

This really should be number 1 on the list - because it is really caused by laziness and the desire for "easy money". Trading ain't easy. Running my catering business with it's cranky brides, broken equipment and moaning employees is still easier than trading. Got that? Depending on your method and timeframe even a good system will experience flat periods or drawdowns lasting weeks or even months! If you haven't tested this thoroughly then you are doomed! You think it's gonna be easy to lose again and again over a two-week or two-month period. Are you still going to be as eager to take the last trade as the first? You'd better if you want to make it! It's like I told a guy last week - the market pays me to take a licking for 8 out of 10 times so that I can really beat the living $#*&! out of the market that 1 or 2 times and make it all back and then some. Even scalping has it's dry periods - nobody is immune.
5) When do I get out of here?
A couple weeks ago I was working with an aspiring trader and we were simulating (tick by tick) exactly how I do my trade setups. I encouraged him to try some of his trade setups and was stunned. He had fantastic entries (actually they were classic TA such as butterflies and flags)

6) Don't watch the market enough to know anything.
Most of the "back testers" I talk to don't watch their market in real time

7) Lack of persistence.
People who end up succeeding have failed many times. Failures fail once and quit. Keep failing. Keep working. According to what most people say it takes about 3 years to start being successful as a trader. I find this to be mostly true. Actually it's all about hours. For myself it took about 3 years spending an average of 20 to 30 hours per week testing, trading, failing, working...But I'm not the brightest crayon in the box - some folks might figure it out faster. Live breath and eat trading. Think about nothing else. Be obsessed (I sure am). Go beyond work, beyond play into simply being.

Another ever so common problem. I hear "I got into Forex because of this stupid course and now I want to learn how to trade Forex" a lot. And not just for Forex. It is so important that your methodology, your psychology and your checkbook all support your market and timeframe. If you choose a market and timeframe arbitrarily you will get less than ideal results. I wouldn't try to scalp the Urea market for 2 ticks and I wouldn't try to swing trade the mini S&P. Why? Because they are not the ideal markets for those activities (unless you have a seat at the exchange for the Urea market I suppose). Also I wouldn't look only at daily bars for a scalping setup or at minute bars when I'm swing trading. You'd think that this is common sense but it's not. Are you trend trading - then look for markets that trend frequently (i.e. currencies). Are you interested in volatility based trading - then look at volatile markets like the DAX and ER2. Nuff said.
9) Lack of decisiveness.
Usually there is a reason why we lack decisiveness. It's because we haven't thoroughly tested our idea or become confident with trading our style. I strongly encourage simulated real-time trading to solve this problem.
10) Afraid to succeed.
Weird huh? With a capitalistic society you would think we wouldn't have this hang up. Is it because trading looks physically easy to do? Is it because it is hard to see how it benefits society? Is it because we are unsure of ourselves? It is an interesting dilemma. But I ask you this: What is your contribution to society from your day job? If you are in an office you push papers for someone (either the government or commerce) - who do you really help? If you are in retail, construction etc. your work may have more obvious effects. Most people find it hard to overcome this fear of success in the markets because the markets have no limits. None. In the next minute the Russell could go up or down 20 points and you and I have absolutely no ability to control it. Your account can go down to 0 (or worse) or increase by millions depending on how you manage it. In no other job are we so empowered (our income can be limitless) and yet so fearful (we can also have negative income). Trading is about freedom - and freedom can be a scary thing. Are you sure you want to be free?
Edward
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