There is a risk with investing in everything.
The risk with investing in cryptocurrency is that it is a relatively new
technology with a high percentage of owners speculating on its performance.
It has proven to be volatile in the past with Bitcoins biggest crash in 2017 - 2018.
It is known that there are many factors and events which have and will continue
to cause market fluctuations thus affecting the value of Bitcoin.
History
December 17, 2017: Bitcoin's price briefly reaches its all time high of $19,783.06.
December 22, 2017, Bitcoin fell below $11,000, a fall of 45% from its peak.
January 12, 2018, Amidst rumors that South Korea could be preparing to ban trading in cryptocurrency, the price of bitcoin depreciated by 12 percent.
January 16, 2018: Bitconnect announced it would shut down its cryptocurrency exchange and lending operation after regulators from Texas and North Carolina
issued a cease and desist order against it as it was suspected of being fraudulent. Bitconnect loses 92 percent of its value within days.
January 26, 2018, Coincheck, Japan's largest cryptocurrency OTC market, was hacked. 530 million US dollars of the NEM were stolen by the hacker, and the loss
was the largest ever by an incident of theft, which caused Coincheck to indefinitely suspend trading.
From 26 January to 6 February, the price of Bitcoin halved, and reached 6,000 US dollars.[citation needed] Additional negative news for the cryptocurrency market
continued in the first quarter of 2018. The price remained low though the level slightly recovered in the first quarter of 2018.
March 7, 2018, Compromised Binance API keys were used to execute irregular trades.
Late March 2018, Facebook, Google, and Twitter banned advertisements for initial coin offerings (ICO) and token sales.
November 15, 2018, Bitcoin's market capitalization fell below $100 billion for the first time since October 2017 and the price of Bitcoin fell to $5,500.
https://en.wikipedia.org/wiki/2018_cryptocurrency_crash