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One of my stocks dropped 40% in 2 days, how should I mentally approach this?
Have the reasons you originally purchased the stock changed? Is the company still sound? Does the company have a new competitor? Has the company changed the way they operate? If the company is the same, except for stock price, why would you change your mind on the company now? ESPECIALLY if the company has not changed, -- but only other people's PERCEPTION of the company, then your original reasons for buying it are still valid.  In fact, if you are not a day-trader, then this COMPANY JUST WENT ON SALE and you should buy more. If you are a day trader, then you do care about the herd's perception of value (not true value) and you should sell. DAY TRADER = SELL BUY AND HOLD (WITH INTELLIGENT RESEARCH) = BUY MORE