The Triggertrap Ada Kickstarter campaign launched between October 2012 and October 2014. That means that this is the version of the Kickstarter Terms of Service that applies to the Ada project.
The Terms of Service states that
Project Creators are required to fulfill all rewards of their successful fundraising campaigns or refund any Backer whose reward they do not or cannot fulfill.
A few of our backers were reading the above mentioned clause as the campaign having to offer a full refund. However, the ToS doesn't specify that a failed project should offer a full refund - it just suggests that a refund should be made.
In our opinion, partial refunds is the only interpretation of those ToS that makes sense: If the ToS stated that creators always had to refund all backers in full in case of a failed process, the full burden of the project would be on the project creator. On Kickstarter, you aren't buying things that already exist — you're helping to create new things, and Kickstarter exists to give creators a chance to take an ambitious leap at creating projects, products, and artworks that would otherwise have been impossible. Should a full refund be due in the case of a failure, nobody would use Kickstarter.
After taking legal advice, we believe the terms of service means that we should offer a refund of the remaining funds, so that is what we are doing: Offering a refund equal to the money that's left from the Kickstarter campaign, distributed proportionally by their backer level - in other words, we are offering everyone a 20% refund.
Link to this FAQ entry: http://tri.gg/ks-refund-tos