A few months back I wrote briefly about the risks attached to crowdfunding. Those risks are underlined in this article by the BBC's technology correspondent Rory Cellan-Jones. Kickstarter have admitted that while their requirements are a little more stringent than other similar platforms, they don't verify all of the claims made by creators: "Creators are responsible for their projects, and backers decide whether those projects should be funded. We encourage backers to do some research on the creator and their project before backing, and to evaluate their ability to complete the project." So, essentially, due diligence is down to prospective investors.
However, while investors can't necessarily expect results and consequently a return on their investment, they are at least entitled to good communication from those they're helping to support - something that creators would do well to remember.