Using a large survey with 47,188 backers of Kickstarter projects, I examined the factors that led to projects failing to deliver their promised rewards. Among funded projects, a failure to deliver seems relatively rare, accounting for around 9% of all projects, with a possible range of 5% to 14%. There are few indicators at the time of project funding as to which projects might ultimately fail to deliver rewards, though small projects (and to a lesser extent very large projects) are more likely to fail to deliver rewards, as are some project categories. The demographics of project creators (including gender, education level, and family status) did not significantly affect the chance of a project succeeding.