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.
The method of selling tokens through ICO was indeed largely abandoned by the developers team even though there were still some who sold through the ICO because ICO's reputation had deteriorated after many ICO scams. For investors, the IEO promises advantages and certainty of listing on the market, and that is because IEO is more attractive than ICO