I also agree with your opinion when prices up some people waiting for when the price down and they want to buy that time . on the other hand fud and panic sale also major reason for price down .
Yeah it is human nature they use become worry about minor things and the same they do with bitcoin, they get effect by the fake news and fads about bitcoin decreasing price, they become impatient and finally they sell at panic price and suffer lose, after few months when they see price increasing then they feel how bad they have done but no use to cry over spilt milk so its better have patience dont sell at panic, it causes the price down.