Crypto currency is highly dependent on various news. The slightest negative news can greatly affect its course in the direction of decline. Such negative news, including counterfeit news, may appear at any time and the rate of bitcoin and the general market of crypto-currency will fall.
Secondly, a large number of bitcoins can be thrown at the market at any time for sale. It is believed that the last drop of bitcoin in December-January was due to the fact that a certain Mt. Gox from Japan sold three large batches of about twenty thousand bitcoins. This can happen again at any time. And not only when bitcoin reaches a temporary price peak. Sometimes people sell their bitcoins at any time due to the urgent need for money.