It's a dangerous thing.
My plan is to accumulate on weakness and that's what I need to do. But then I get bored.
Yesterday I bought a 1/4 position of FAS at the closing bell. It was a gamble on the JPM earnings play, which they destroyed by the way. But it was dumb. I didn't really think about it. I did it because I was bored and undisciplined.
I managed to get out for a small gain that did little more than cover my fees. I was lucky though. The market was obviously flooded with sell orders on the open. I could have got had, badly.
Stick to the plan. Accumulate on weakness.