Some investors that invest huge amount of money to trade crypto-currencies in the trading market don't hold their crypto-currencies sometimes because they do not have the confidence to believe that the trading market will eventually recover someday, that is the reason they are selling their crypto-currencies away to reduce their overall loss.
actually such people are very new in trading and they do not have enough experience in trading, in fact they need to spend some good time in trading bitcoin and other altcoin so that they may know the nature of bitcoin and other crypto currencies, and only then they can trade in a better way.