Market validation and iterative development for hardware can take a long time. Product developers are jealous of the fast iterations involved with software development. I've recently learned that despite being lower quality, people value the novelty of 3D printed goods. And we know that consumers value co-creation .
We know that early adopters tend to be early adopters of multiple kinds of technology. So if your user base for a new physical product also largely have 3D printers, you could bring your users into your prototyping process. Send out 2+ versions of your product without them knowing which version they received.
You can ask for feedback within 2 days of pushing out a design with real users. From the feedback you can start a new iteration, which you can then push out to your users as a tangible update within a week. You could even pay for the small cost of material used.
This platform could start with STL files, and then in the future use a common 3D printing API such as the one we're building called PrintToPeer. Early adopters would even be incentivized to get a 3D printer to be a part of the development cycle of new products.