With smaller accounts commissions do play a big part. One might be forced to gamble to catch a bigger break. Instead of selling 1/4 one might have to sell 1/2 or try holding out longer.
Averaging down can be tricky. I think its fine to avg down on a stock thats in a long term uptrend but otherwise it can be a recipe for disaster. You can get away with it many times but the one time you get bit can ruin all those times getting lucky plus some.
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