actually in my opinion the rise and fall of bitcoin doesn't need a reason. bitcoin is indeed like that it can rise quickly and fall abruptly. but in my opinion sometimes the bitcoin market can also be influenced by the news. if there is positive news about bitcoin then the price of bitcoin will tend to rise. conversely when bitcoin is attacked by negative news or FUD the price tends to go down. and news about the Chinese president who supports blockchain technology is making bitcoin prices go up. because most investors and bitcoin miners are from China.
It has to be a reason, everything has a reason and it includes the rise of bitcoin. Volatility is not the only reason on its changes in price. As we can see the latest updates in cryptocurrency there is some good news and this leads to its price in sudden increase. This may be because of the announcement of the Chinese president regarding the adoption of blockchain technology.
You're right cause there's always something that triggers the trend posed by the crypto but I don't see any reason why the announcement made by the Chinese President would be the reason the increase in the price of the crypto market causes their government still haven't endorse cryptocurrencies.
Nobody will know real reason as usual. blockchain is a chaos
That's what you believe cause you don't have the depth understanding about it and its blockchain is chaos some of the government won't have endorsed it in the first place.