The price action would change directions. It takes time to get into a position and time to get out. Popping up order screens, entering passwords, the time it takes to be filled. A stock can turn on you and go 20-30 cents against you before you can get out of it. One time I just used a market order to get out and there was one of those dogone down-spikes and my order executed 50 cents below the price that was current when I started entering my order. The price was only down there for a few seconds and then popped right back up to where it was before. Including trading fees I lost about $100 on that one. What I did after that was to use sell limit orders to protect myself from those spikes. The first time I used them happened to be one of those times when the price drops like a rock. I entered a limit of 5 cents under the current price, fingers flying over the keyboard, but by the time my order went live the market price was below my limit, so the order didn't execute. I had to enter a password to cancel the limit order that wasn't going to work and then enter another limit order at a nickel lower. The same thing happened again, the "last price" was lower than my limit by the time my order hit the market. I had to cancel that one and enter another order. This happened four times in a row so finally I just entered a market sell order and got rid of the stock. I think I lost about 30 cents a share on that one, with trading fees I lost somewhere around $65. My trading fees cost me $20/ round trip. Because I wanted to be consistent and enter my trades at exactly 9:35am I could only do one trade a day, and even if I had of entered two or three positions I would have had to be able to manage them all, no way. They can really move fast in the first half hour. I decided that my skill and/or my trading software were just not up to the task. The whole deal was just to volatile and unpredictable, too fast. The problem was time. It takes time to get into and out of positions.
Here are a few trades I did. I think it the dates, etc are correct.
HAIN 5/11/01 net +$302.00
JCOMA 5/14/01net +$97.00
BRCD 5/15/01 net +$14.00
NCBC 5/16/01 net -$75.00
PPDI 5/24/01 net +$61.20
AREM 5/25/01 net -$23.54
CTLM 5/29/01 net +$140.27
JNIC 5/30/01 net -$109.14
CTXS 5/31/01 net +$50.02
PHCC 6/01/01 net +$186.49
TUTR 6/05/01 net -$39.84
Hope this helps, maybe you can do something with it.
PS- I only entered the trade if the price was moving upwards.