It's not really so strange. A common theme I've seen on kickstarter projects is that they come up with product Z. They find a supplier in China who gives them quote X. But they will also need some money for themselves (not being greedy but just a living wage so they can quit their jobs and work on this full time) so we will call that Y.

However, after they collect the money the supplier says - actually it will cost X+N dollars. (X+N) + Y > the kickstarter amount. Perhaps they also found other issues which will cost extra money (perhaps needing to hire another developer).