Just because startups as businesses generally fail, doesn't mean projects (which is more what Kickstarter launches) must generally fail. The metrics are totally different. While a startup needs traction, growth, and all those other difficult things, a project faces much more concrete objectives.

Honestly, if the creator is realistic with expectations, goals, and required funding, it seems to me most every project on Kickstarter ought to be able to complete and thereby succeed. Not many are truly speculative "This could turn out to be impossible" sort of affairs.