You might be mistaken about ICOs and failed projects being in same classification, a scam ico is one who from the very beginning has the intention of defrauding its investors and other stakeholders. A failed project is an ICO which unfortunately was unable to deliver on its promises due to various reasons. The same thing happens not only in ICO but in every investment as well. You might invest in a product but failed to capture the market, this is part of the inherent risks of spending. What you can do is to only minimize such incidents to a bare minimum for you to be able to profit from your investment.