There are too many non-transparent ICOs
There are too many non-transparent ICOs. Their unrealistic promises to contributors displace legitimate TGEs in the market. That's one of the reasons why the crowdfunding industry needs to be regulated on a practical level.
Economics provides us with a theoretical explanation for the current dilemma. It is the so-called “lemons problem” referring to problems arising from asymmetric information. See: "The Market for Lemons."