Quote from sucre_estave:
Here's a few that cost me thousands:
1. Waiting for a stock that had just broken out of a base that day to come down 15 cents so I could save 90 bucks. It never did, so I let it go and of course it took off. I kept tabs on it and traced the point were it started to give sell signals, 24 dollars higher than when I quibbled over 15 cents. Moral: you're playing for gains of 25% or more - don't nickel and dime yourself over a few bucks.
2. Selling a stock the first time it made a new high on low volume. This IS a sell rule, but it is tough to judge and must be put into context - was the market low volume that day? How far along is the stock from its breakout? Is the market strong or shaky? Is the stock starting to sell off hard? I netted 30% on the sale, nothing to complain about, but the REAL sell point would have netted me 160%.
3. Buying ANY breakout of a strong fundamental stock. You really have to analyze the price/volume action in the stock's base to judge its liklihood of success. O'Neil goes over this in his latest book "The Successful Investor", but it takes practice to learn. I bought several breakouts from bases that were poor, and they quickly turned into losers even though their fundamentals were great.
4. Waiting too long to sell. While I never violated any stops, a few times I could have gotten out earlier when new buys weren't working rather than waiting for them to fall 8%.
5. Buying on a return to the pivot point. A stock I loved gapped up past the pivot on the after hours session following its earnings announcement. I never fool with after hours trading, so I was just disappointed. About 2/3 days later the stock sold off so I thought I was the luckiest man on the planet to get it right at the original pivot point. Needless to say it kept falling and stopped me out with an 8% loss. While I imagine you could buy a stock if it just drifts down to its pivot in light volume if the market happened to be selling off a little, I prefer to avoid it if I miss the stock heading up.
6. Holding on to a breakout even though the breakout day's volume didn't end up 50% above average. While sometimes the breakout still holds up, the odds are better if the volume is very high.
I was lucky to do most of my learning in a bull market last year. Unfortunately I wasn't applying the strategy until mid April and missed the start of the rally in March. I might have managed a decent profit even with my bonehead moves.
Hope this helps.