Here's the hard lesson people who raise money for hardware on Kickstarter must learn

Just because you have a prototype, you don't have a product. Trust Ayah Bdeir, founder and CEO of littleBits, who knows the challenges that it takes to to go from idea to mass market product.

LittleBits is a circuitry set that has been stripped of the scary wires and traditional yellow colors and turned into a simple set of modules that anyone from kids to entrepreneurs can use. Some people using littleBits have made everything from a marble sorter to a voice box that plays back a father's recordings.

But making one of something isn't enough.

"The hurdle between a one-off and a mass manufactured product is still pretty big," Bdeir said at the Bloomberg Businessweek Design conference. "Because once you push a button to make 10,000 of something there is no turning back. I think that's a hard lesson that a lof people who have raised money on Kickstarter learned."

Bdeir found this out when building littleBits. The company wasn't funded on Kickstarter, but Bdeir still faced the challenges of scaling to a manufacturing level.

One problem Bdeir ran into was the magnetic connector that links the circuits together.

"This was before the MagSafe came out," Bdeir said. "The idea of putting a magnet in electronics was hard." The machines were metal and you can guess what happened when you tried to put magnets through an assembly line. It took adding a covering to the magnet so it could be injected into the set during the manufacturing process.

Bdeir doesn't want to deter would-be entrepreneurs from prototyping, but just to be realistic. "Have the conviction and bake in some time."