Probably whales are cashing out and the middle to low volume holders did followed with the hype or has a feeling of FOMO. Majority of the listed coins on the coinmarketcap were all affected and there's no one that can avoid this thing. On these days the best thing to do is to wait for it's increase or while waiting for that pump again and greener pastures, take the ride of buying your desired coins because after this it will really pump.