It is natural human instinct to follow the crowd, but when trading stocks that may not always be the best thing to do. One argument states that if everyone else is selling, then you should be buying, and if everyone else is buying, then you should be selling. A successful trader knows how to see a trend before it begins and therefore can sell / buy before the masses do. However, some people find it difficult to break away from the crowd- they find safety and comfort in numbers.

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