I'm curious where the costing came from (since $30k barely pays a good designer for a few months). The reason for asking is that I'm wondering why the original goal wasn't higher? Is it really that you didn't forsee that level of support? This is a common reaction from startups that are amazed that their $10k goal suddenly spiraled into millions. Often the reaction is to add lots of unrealistic stretch goals which delay the project.
As for most backed, I think relaxing the early bird deals clinched it for a lot of people (including myself). I have a lot of respect for Kickstarters that offer a flat pricing for the base product.
It comes from using Kickstarter primarily as a marketing platform and as a funding source secondary. These campaigns are created with an insignificant "funded" threshold knowing very well that they'll be funded a few hours into the campaign. See for example the Reaper Bones [1] annual campaigns that set a very low bar, expecting very well to hit a million from the get go. It's a great way to get many eyeballs on your project and make a few bucks as well.
Though to answer the second question: there are plenty of cases (usually hardware) where people really underestimate how much things cost to make. I've lost count of the number of stories where startups said "We messed up our mold/printer/fab order which cost us $20k to redo, and then we had no money to make t-shirts".
Estimation is key on a Kickstarter. We've got a team of 4 of the best designers and developers I've ever worked with who can deliver beautiful, usable products on time.
It's the highest compliment I can pay them professionally.
Absolutely true when you rely solely on kickstarter for your funding, which is a pretty precarious situation anyway unless what you're doing is simple or inexpensive.
As for most backed, I think relaxing the early bird deals clinched it for a lot of people (including myself). I have a lot of respect for Kickstarters that offer a flat pricing for the base product.