For me it's leaving money on the table, rather than losing more money than I should have. Such a mentality definitely screws with how selective I am with my discipline.
It think missed opportunity is the hardest thing to deal with. Like wanting to by a stock at 40, but then at the last minute deciding against it. Then before you know it it's up $3.00. I can deal with losses, but missed opportunity is the most difficult thing for me to deal with. I did my work, I was right, but I have nothing to show for it. It's very aggravating.
That stuff used to bug me, until I realized I did not have the power to predict the future (darn). What I fight on a daily basis is the urge to trade outside of the system. My wife calls it gambling genes.
I should've added that as a selection in the poll. I've done that several times, and I've always gotten screwed.
I fell into the trap that it is better to have a high % of winning trades than to cut losses and go on to the next trade. When I was trading one index, I would get a run (not unexpected) of losers (I did follow the signals) and worry that my system was failing. Then I would stop trading and look for ways to improve my system. I finally got to call this trap, the curse of being an engineer. While practicing engineering, we were always looking for the optimal solution. This unfortunately carried over into my system development. The real trap was I almost always would find a better system, but while looking for that better "mousetrap", I was missing a bunch of winners that the orignal system generated. So, mentally I felt better because I found the more perfect system but it hurt where it mattered in a lower account balance had I kept trading. I never really developed the mental discipline to overcome this. What I did was scrap the one index system and go to a system that trades about 90 stocks. This way I never really worry over a trade as I'm only putting less than 4% of my account into any single position (typically I'm in about 30 positions at a time)and the risk/stop point for each position is less than 0.3% of the account. Also, there are longs and shorts so I'm somewhat insulated from overall market moves. When a signal comes, I take it and I don't fiddle with the system as each day I get winners to go along with the losers. It runs about 50% winners. DS
Losses = Who cares..can`t get avoid them. Winners = No big deal...NEXT! Missed opportunity = there will always be another trade right around the corner Not adhering to my system is the killer that makes me want to drink!!! Thankfully I don`t drink that much anymore.
I am a discretionary systems trader i.e. I trade with discretion in a systematic way... thinking beyond the parameters of my various systems is what invariably causes me grief... so I totally agree with both indahook and peterfigliozzi... thankfully, it only happens rarely these days (positive reinforcement of what not to do over the years)...
Re. leaving money on the table, Baron Rothschild, when asked why he was such a sucessful investor, replied that "I never managed to buy at the bottom and I always sold too soon". There are always more trades. Jessie.
I do strive for efficiency. Soooooo...lol.. I debrief and often notice loss of efficiency. Today I have two stocks below the 65 day av vol; meaning..lol... One did make me 3% but the other is a day (guess ...lol) away. The others are heart warming. 4 to 7 times av. so they are riding into peaks soon. KMX and SAPE. Right now my accounts are messy too. Being lazy I like them all to have about same stocks in them. I took a couple of fliers to just get what it feels like to own a couple and stay focussed on newbies. I also hate the feeling of not getting through to others.