How do you know the exchange price after ICO?
For example Qtum. At first the price was 0,35$, Later it was $6,-
It only depends on the hype and speculation around the coin after launch. hard to predict but usually the bigger ICOs end up with higher profits.
You are right hype and speculations during and after ICO is very important for the price and effect directly but other important points are the dev. and the progress of the coin. If the dev. is professional enough and the progress is satisfactory you can also see the rise of the coin's price even before the entrance of the market.