Bitcoin and cottage plummeted, there is no investor concerned about the market? Is there a big picture for the old players to give some advice? 
Cottage? Which cottage plummeted? lol
Jokes aside, I think the recent rumor that India was banning Bitcoin (which turned out to be just a false rumor), and the drama that Tether's auditor left them without performing an audit, then U.S. regulators from CFTC sent subpoena to Tether and Bitfinex, all contributed to what's happening on the markets now. But then again, markets can go up and down without any reason at all...
Looking at the bigger picture, I feel there's a lot of room to grow for cryptocurrencies as a whole. For Bitcoin, there are quite a few proposals / projects that are under development to improve scalability, privacy, security, and adoption. Here's a short article from Bitcoin Magazine listing some of them : https://bitcoinmagazine.com/articles/keep-eye-out-these-bitcoins-tech-trends-2018/
So I'm not worried about the current price drop. I think we have an exciting year ahead of us.
