Many people who lack understanding of the market and prefer to believe every rumor in the decision to sell Bitcoin that they had made it up because they are afraid of pricing conditions deteriorated but notice that the price of Bitcoin could rise again in the future.
Those people surely are not patient upon seeing the price to fall and they will do the same thing as those dumping people did. Because they fear that probably the price will go further to fall and they don't know too that it can do come back on higher price so instead of just holding, they do panic selling. I'm one of them before.
Its normal especially to newbies in bitcoin and trading to panic when the price is going down. They tend to do that because they lack experience and enough knowledge about the nature of bitcoins and trading. But the longer they are in the business and their experience becomes wider then they will no longer panic and just do proper trading leaving strong emotion aside that impedes their judgment.