In general, most of the ICO project is hype, so when they open, is the highest price, then can present a gradual decline, that is why I am not willing to invest ICO, most of the ICO is bubble.
some ICOs are having their prices declined due to investors are already getting enough profits but the crypto price is indeed unpredictable because nobody would know when will the price Wil increase or decrease.
But most of the time, after ICO and they bumped into coin exchanges, they will soon rely on it's marketing and development team because the effectiveness of the project is the most basis on the price value.