While some Kickstarter projects result in many happy customers, and your blogger has funded several Kickstarters that succeeded fully, while at least one has fallen short, there is the risk that a Kickstarter project fails without giving out any rewards.
DPReview reports that Dr. Rudolph's APO Plasmat Lens 105mm f2.7 by Meyer Optik was one such project. The company behind the project filed for bankruptcy, leaving those funding the Kickstarter with no rewards and no chance of recovering their funds. The starting pledge was US$ 1,049, so there are probably some unhappy customers out there right about now.
A contributing factor may have been a traffic accident involving the CEO and main investor for the company, Stefan Immes.
