I agree with you the IEOs is not guarantee will make successfull our investment in cryptocurrencies or there is no guarantee that the IEOs is more good than ICOs, i have got bad information about the scam IEOs
https://news.8btc.com/worlds-first-ieo-exit-scam-yescoin. That's sad news about the IEOs projects so we don't say that IEOs is more great than ICOs if we don't know anything about the projects because there are no free risk investment in cryptocurrencies, we must becarefull when research IEOs projects or ICOs.
I have not heard of IEO fraudulently before. This happens, most likely due to the use of little-known exchanges that do not thoroughly check the project for legitimacy. I think such cases will happen, but in this case, the exchange should use the services of insurance companies so that investors' money is insured.