Based on some of my observations the reasons why some ICO project fails is because of the lack of clear  and concrete plan. This leads to not gaining the interest of investors hence will lead to the project's downfall. Every ICO project's whitepaper should have the clear and concrete information about their vision, the team, the project, the road map, development and timelines and the what's in it for the investors, that way we can gain their trust and confidence on the project.