maybe some of them getting tired and don't want to invest in ICO because situations in the market are not stable and make them cannot make a profit. but the other investor still trying to invest in ICO because they believe that the situations will not stay for a long time and after bitcoin makes a new stable price, then it is time for the ICO to rise again. and we can see that many ICO delay their time to finishing the ICO because they still want to attract more investor to come to their project and invest their money.