As I prepared to turn off my computer yesterday, I noticed a huge dive of the crypto prices. Or maybe I got used to a certain calmness of the market and two-digit drops suddenly seems unusual. I didn't investigate at the time the reason behind all this, because well, I wasn't going to sell and wasn't going to buy either on the spot. So, knowing more right then wouldn't help much...
But this morning, seeing that the prices were still down, I searched for what caused it.
There is quite a bit of confusion, and probably nobody really knows for sure, especially since the total market capitalization and trading volumes dropped significantly over this extended bear trend, so it's easier than before to make the prices jump all around.
But, the above fact aside, there are two recent events which may be correlated with this dip.
One reason that could have triggered the plunge would be the hack of a South Korean exchange called Coinrail, and the loss of 30% of the coins traded there. Despite the regrettable incident, I think this exchange is not large enough, so the impact on the prices can't be for a longer term, using this as a reason.
Another reason that was connected to this dip, is represented by the subpoenas sent to the exchanges Bitstamp, Coinbase, itBit, and Kraken, in relation to CFTC's investigation of bitcoin price manipulation. While this could have determined some short term volatility, I believe such an action is beneficial on the long term.
Price manipulation is obvious for a while now, and there's no barrier holding back a bad actor to do it. Additionally, the conditions on the market, the size, the apathy and so on make it very vulnerable to such actions. As long as the counter-measures don't crush the yet fragile market, they are needed.

Personally, I stopped watching closely the price movements of cryptos for quite some time. Today, I found a good opportunity to buy a little more bitcoin (and with it maybe Steem). Nothing major.
Something that my friend Jon ( @jongolson) would call dollar cost averaging (not something he invented, it's a well-known system you can use to invest, if you don't want to worry about price fluctuations). A system he's a fan of, except I can't afford to buy regularly and regardless of the price, so I pick some moments and buy, but with small amounts of fiat.
For me there are two possible scenarios. Price goes up. Great!
Price holds or goes down, I'll keep buying tiny chunks of crypto.
At least this is my plan now. So, markets red? Great! Markets green? Great! Lol, wonders of HODLing!