I found a very interesting article about the development of prototypes on the Berkley Sourcing Group’s website.
It sums up nicely the technologies and the challenges associated with prototyping plastic products, metal products, and cut & sew (textile) products.
It also warns against the danger of spending too much time refining successive prototypes:
The purpose of the prototype is not to make a perfect prototype. What are you going to do with that except admire it? The purpose is as a tool to help you make decisions about your product. So, before you rush into it, make a list of questions that you expect the prototype to answer for you. Marketing questions? User interface? Functionality? Materials? Every product will have different areas of concern. Focus on those when you are making your prototype instead of just trying to make it perfect.
We had a client who spent 12 years making a prototype! I’m still not sure if he has completed it. Unless you are doing this as a hobby, remember the goal is to take your product to market. Be focused on that goal through all stages of the process, but particularly when working on the prototype. This is a common black hole for inventors and small businesses from which many never escape.
I also saw this phenomenon at work. A company finds a factory in China and starts developing the prototype of a complex metal product. It is never good, the factory loses patience, and it takes longer and longer to see a new version.
And then, when (and if) it is finally acceptable, the battle to get it right in production just begins…