not all the IEO gets sold out. this is exactly the reason why they were also doing bounty campaigns here in the forum even after getting approved to do IEO with an exchange.
they must have thought its going to be easy to promote a token sale when doing an IEO for the exchange can send out mass emails to its users but the fact that we do use throwaway emails on exchanges, they are never gonna be read.
Unfortunately, after the appearance of this innovation by the IEO, my email is overwhelmed with spam from the exchanges's news. I advise you to participate in the IEO on major exchanges, this is more reliable. Investors when conducting an IEO limited by conditionsin certain by exchangers then your funds will be blocked on the exchange (if you are the citizen USA for example) . they must have thought its going to be easy to promote a token sale when doing an IEO for the exchange can send out mass emails to its users but the fact that we do use throwaway emails on exchanges, they are never gonna be read.