Currently IEO's are becoming pupular and providing a more reliable option for new projects than ICO's. Previously a lot of new projects started by raising funds via their ICO sites and because of unregulated nature of this avenue, a lot of scammers used the medium to swindle a lot of victims.

Now the story has changed as it only serious projects that would want to go through IEO's, we no longer would hold only the project body responsible for any IEO scam but the exchange, so any exchange that values its reputation and users should do a proper scrutiny about any project before accepting their IEO sales. For instance if an exchange fails multiple times with their IEO, it will drive attention away from them, that is why Binance still draws a lot of attentions because it has recorded more successful and profitable IEO's.