They aren't investment opportunities as much as scammers want people to believe they are. Until there is some regulation on the ownership of companies like and shareholders rights through ICO's (their aren't any currently), these it is best to stay away from.
Some pretend it's an unregulated stock market, which allows for partial ownership of a company. Initial Coin Offers are just non-refundable, zero ownership rights tokens to represent something a "team" plans to build. Whether they build anything or even have a good idea are vague at best with most of these.
It's a great way for people who can't raise money through IPO's, banks or venture capital to pretend they will start something and basically steal people's bitcoin.
This is true most of the time. YOu cannot blame ICO though. You can blame people for being so stupid they can't google before investing. It is alwyas like they do not like their money or did not work ver yhard for it or something. How many hours of work do they put in to make that money and they cannot even take a minute to google something. No sorry I feel nothing for these people. An ICO is still a great way to raise money for things and if the company does carry on like it should your tokens will carry value if it's shit then the company will die or even never exist. This is why you should only invest in an ICO you can see progress with and they have something to show for it or at least they are trying. Copy paste ICO are not worth wasting time on.