If I am not mistaken, by the end of 2018 the ICO project has been abandoned by many parties for various reasons that have emerged and turned to the IEO.
Yes. They turned to the IEO because it was more reliable. Investors can buy coins directly on the exchange. While ICO, waiting for the distribution of tokens by the team. Because many teams fled after the ICO was finished, the confidence in the ICO began to diminish.