Because of there are so many bad news related to Bitcoin come everyday and the whales are publishing bad announcement from famous people to speard FUD to make trader and holder feel nervous then try to cut their loss by selling with lower price. And the worst news come from China, the biggest country where all the biggest Bitcoin mining factories in the world located in.
Many people disappointed in the moves, believing the the fall of bitcoin is happening because of market manipulation. But we must remember that the real value of a cryptocurrency is not driven by price but instead is driven by utility.
More like driven by spaculation that there MIGHT be an utility use in the future.
I agree that there's no market manipulation though, at least not a conscious one. The news media will cheer when something has already risen which will result in FOMO traders buying and overpricing things, then the same news will FUD when something is falling panicing people and making them price go underpriced. I don't believe the media is doing that to manipulate the market, but because they're just saying whatever the audience wants to hear in order to keep the viewership numbers high.
Here's what I am seeing on coinmarketcap.com:
Crypto prices all going up and down in almost 'identical' patterns. Percentages of the top 100+ market cap coins that mirror each other and go up and down almost in unison.
To me, this tells me there is BIG money, possibly by one or a few whales in a lot of these tokens/coins. Their bots or traders put money into all or most of these coins at once, creating an illusion of a bull market return. For all of these coins/tokens to go up on so many tokens, in unison, and then go back down in unison, is pretty obvious what's happening.
Yes, the market is driven on news and emotion, but look closer - these patterns of up and down prices on coinmarketcap.com and Coinbase are following each other too tightly to be just news driven.
Plus, there are 'Pump and dump' groups pumping a lot of coins, then dumping for profit.
Please allow me to point a misconception that exists about "identical" patterns.
If you're viewing the crypto prices against fiat currency (EUR/USD etc) then there's a technical reason why almost everything is going either up or down every day. Since the price of every coin is relative to the price of BTC (the altcoins are translated to an
xamount of BTC, which is then translated to fiat), even if the 99% of the market doesn't move and only BTC increase by 10%, then coinmarketcap will show a 10% increase of every altcoin.
e.g.:
ETH = 0.064 BTC
BTC = 7400€
so 1ETH = 470€
If no one trades ETH for 1 day and BTC goes to 14800€, then ETH will still equal 0.064 BTC, but 1ETH = 0.064BTC = 940€ (it doubled as well)
TL;DR,
If you want a clearer view of altcoin's movement, check their price against BTC.