It all depends on the coin or ICO.
Some early investors get huge discounts on pre ICO sales, prices that little guys will never see, they often dump these coins for less than the ICO price immediately after the ICO is finished for quick gains. When this happens, ICO investors get the shaft (at least until the demand picks back up).
I also favor for these type of ICO which have a high discount in the start as after the end of ICO they when come to exchanges then they are on their high rates and at that time if you sell that tokens then you will get a high profit. These type of ICO have got much crowd of investors and they all are satisfied with that.