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.
And is wrong because that's what the person might also react on other things, by always being afraid of something that might not even happen, when they actually referred this to the real world I no that some of those people will be saying that is not the same as ordinary investment but the truth is that even if they are not in the same market but the behavior someone has on any of the other investment is going to be the behavior they would definitely have on anyone they do, so is good to start learning how to endure when things are not working on their way, besides there wasn't need to be that scared because since other are also enduring.