Not all of them are scam, but there is a possibilities that fraudsters might use the ICO scheme to mislead people. We cannot judge them because new ICOs are something new that are just about to be started its development. All I can suggest is it is better to be cautious because there have been a news circulating that scammers/fraudsters are abusing the use of ETH or Smart Contract based system to make a too good to be true projects. And also do not just look into their promotionals/advertisement about their coin/token, try to read their whitepaper and try to discover some holes into it and try to have some critical thought. The important part of the new ICO is they display who are those developers are with them, their roadmaps and initial milestone and also what are the biggest infastructure/company they have been tied up, by that you will able to make a self investigation and asking questions for those who are yet able to participate the initial offering of the coin. You don't need to be rush investing in because of the  time limits they set It is better to know them before we dive into their projects, than you waste a money into new ICOs that you are not really sure if they are worth investing with.