The Open Locksport kickstarter is one notable disaster: https://slate.com/news-and-politics/2012/10/schuyler-towne-a... Back in the day there were an endless series of "$100 3d printers". Etc etc.

Adding the required 50% margin to the BOM of a consumer product is painful and unintuitive. Most kickstarters are done by regular people, and as a normal consumer it can be hard to be appropriately pessimistic when pricing a product you have to manufacture and sell. It's endlessly temping to lower the price.