Apart from selling because of not preparing to invest for a long time, it is so difficult for some people to keep calm when the market is going dip, it just seems they are being cheated or the price of bitcoin won't increase again, and it is not what they can't bear, their only interest is to sell at the moment. One may have plans to go into longterm but the mentality and the understanding towards the market can make one to change a plan when the price of bitcoin goes dip, that is why it is important for any investor to get the real mindset and understanding in bitcoin.