I think it is also due to the fact that there are a lot of people out there that see crypto's as something with a lot of potential but don't understand the technology behind each coin and just invest in multiple coins to diversify. So they put money in on 3-4 currencies and cash out on all when they think the time is right. All does seem correlated and therefore traders will also act like it. The same patterns are repeating itself and there are some traders taking advantage of it.