Because cryptocurrencies based on blockchain technology are not widely recognized!
There are many people who speculate on virtual currency. They think that virtual currency is not only valuable but also undervalued.
This!
The problem today is that most people see bitcoin as a way to make more money (by trading), but the real value in bitcoin has nothing to do with trading, we should see btc more like a stock for the blockchain technology. just like a regular stock price for any company. Price goes up on speculation and when it fails to meet peoples expectations it goes drops. I believe that most people that got into this world at the later stage were expecting a fast adoptation, and wanting to see btc as a a real currency, but as that has not happened yet, people fud as their expectations were not met.