in this time, when the market is unstable and ICOs are failling whole the time, so choosing the time to buy ICO token is very important, if we buy ICO token so soon we may get risks that we will loss money if we sell token on exchange with low price, so it would be better if we wait until the price of token after listed on exchange to buy.
I generally do not see any point in buying coins during the ico company. Why buy a coin at the exchange at a price of, say, 35 cents, if after the leaves are on the exchange, This price will be less than 100 times.