because the quality of the project can also be proven, but if IEO is carried out in several markets that don't have a lot of trading volume I don't guarantee it will be okay,
for example Harmony project is able to compete at the Binance market
There is no guarantee for any IEO or ICO, even if they are getting listed in exchanges such as Binance or Huobi. After all, these exchanges care only about money. Even if some of the projects get rejected after the initial round of screening, if the team puts up a sweetened offer, then I don't think that the exchanges will refuse. I have checked the recent IEOs that are listed in Binance. Many of them looks like scams. Just because a project is listed in the major exchanges, you can't go ahead and invest in them. For each and every project in which you intend to invest, careful research needs to be done. Study the whitepaper thoroughly and get information on the team members before making any big moves.