From the few kickstarter projects I've seen, it seems that there's a lot of people who underestimate the costs of producing hardware and shipping it.
I'm reminded of the story of the guy contracted to write an iOS game. The game itself was trivial to code and he had it up in no time. But then he had to add the menu overlay, high score system, save system, so on and so forth. It's the same with hardware - prototyping is expensive and takes a long time, and you have to think of a ton of corner cases before you make a sample item. Sometimes your plastics or metalworks subcontractor takes weeks or even months to return samples. And if you didn't get it right first time, rinse, repeat.
I'm reminded of the story of the guy contracted to write an iOS game. The game itself was trivial to code and he had it up in no time. But then he had to add the menu overlay, high score system, save system, so on and so forth. It's the same with hardware - prototyping is expensive and takes a long time, and you have to think of a ton of corner cases before you make a sample item. Sometimes your plastics or metalworks subcontractor takes weeks or even months to return samples. And if you didn't get it right first time, rinse, repeat.