By Chris Clapinson | Inertia Product Development
There’s a costly pattern in hardware product development: Teams invest months — sometimes years — into building physical prototypes with care and precision, only to find the market isn’t interested.
Why does this happen?
It’s not because founders or product teams are careless. Often, it’s the opposite — they’re driven, fast-moving, and deeply invested in their solution. When you believe in the problem you’re solving, it’s tempting to think, “Let’s just build it — then we’ll know.”
The reality? Prototypes are expensive ways to answer questions that could have been tested far earlier — and with far less risk.
The hard part isn’t always building (although it can be incredibly hard too) — it’s pausing to validate before building. It feels slower. It feels uncertain. It doesn’t feel like progress. But validation isn’t a delay — it’s the only way to know you’re developing a product that people actually want.
At Inertia, we’ve seen it firsthand: well-engineered hardware products that solved problems no one cared enough to pay for. Before investing in product design, rapid prototyping, or manufacturing, the priority should be proving demand.
As Eric Ries put it:
“The only way to win is to learn faster than anyone else.”
Validating demand before prototyping is how you learn fast — and win.
Talk to Humans Before You Make Things
You can learn more from ten honest conversations than from a thousand hours of product development work.
Start simple:
– What’s the most frustrating part of [the problem]?
– How are you solving it today?
– What’s wrong with that?
– If someone offered you a better way, would you even care?
You’re not pitching. You’re listening.
If you’re not hearing urgency or frustration, you’re chasing a nice-to-have. Nice-to-haves don’t survive in real-world product markets.
Early-stage product validation doesn’t require a prototype — just focused customer interviews and a willingness to hear the hard truths.
Before You Touch a Single Piece of Hardware, Test Demand
You can simulate demand without building anything.
Build a simple landing page. Show a sketch, render, or even a photorealistic 3D image. Add a “Buy Now” or “Pre-Order” button.
Then run ads. Drive traffic. Measure clicks. Measure conversions.
If no one clicks, that’s a signal.
If people click, share, and sign up — that’s a stronger signal.
This is part of the product validation process — without touching tools, materials, or hardware.
Prototype the Customer, Not the Product
Deliver the result — without building the product.
How? Offer a manual version of the experience.
Use off-the-shelf parts. Fake the outcome. Charge money.
If people pay for it in its roughest form, you’ve proven product desirability and business viability.
You’ve also skipped thousands in development costs, and weeks (or months) of sunk time.
You Don’t Need a Fancy Prototype to Learn Something
A sketch. A mock-up. A conversation.
That’s all you need to test usability or explore demand.
Share a crude visual. Ask for feedback. Watch how people interact.
Skip the polished build — focus on whether the concept holds up in the real world.
This is de-risking hardware product development before you even touch CAD software.
Map the Journey Before You Build the Solution
Before designing, understand the real problem in detail.
Ask your customer to walk you through how they solve the problem today — step by step.
Where do they struggle? What do they improvise? What tools do they use?
Capture the pain points. Map the flow.
You don’t need a product to do this. Just curiosity — and a way to listen.
Real-World Examples: Physical Products That Got It Right — Early
1. Ring (Smart Doorbell)
Founder Jamie Siminoff built a mock prototype to shoot a demo video. He used it to gauge demand via crowdfunding. Only after validating interest did he invest in real prototyping and manufacturing.
2. PillPack (Pharmacy Automation)
Before any physical automation, founders sorted medications by hand and shipped them to early users. No tech, no machines — just validation of demand. The approach led to scale — and eventually, a $1B acquisition by Amazon.
3. Brewie (Home Beer Brewing Machine)
The team used rendered images and a crowdfunding campaign to test demand for a home brewing machine. They reached their goal quickly, proving product-market fit before investing in hardware development.
Ask These Questions Before You Prototype Anything
Desirability
– Is this a problem people are actively trying to solve?
– How are they solving it now — and does that solution frustrate them?
– Would they pay for something better?
– How much?
Feasibility
– Can we deliver the outcome now, even without a prototype?
– What technical risks are baked into this concept?
– What’s the path from “it works” to “it scales”?
Viability
– Is there a real business here, or just a neat idea?
– What does it cost to make — now and at scale?
– Who pays, and how often?
– Does this survive contact with reality — supply chains, regulations, margins?
Don’t Prototype the Product. Prototype the Customer.
Prototyping is useful — but only after you’ve proven the problem, the demand, and the value.
Skip these checks, and a prototype is just an expensive way to confirm you were wrong.
Build conviction before you build anything else.
Want Help Validating? Talk to Us Before You Build.
At Inertia, we help founders and product teams prove product value before they spend money building it.
Let’s test your assumptions. Let’s find the signal.
Then — and only then — let’s build the right product.
What Are Human Factors?
Human factors refer to the consideration of how people interact with devices and systems. In the realm of medical devices, this means evaluating how healthcare professionals and patients use these tools. By understanding their needs, limitations, and capabilities, designers can create devices that fit seamlessly into the healthcare environment.
Why Are Human Factors Important in Medical Device Design?
Enhanced Safety: Safety is paramount in healthcare. Devices that are designed with human factors in mind are less likely to be misused, leading to fewer errors and improved patient outcomes.
Improved Usability: When devices are easy to use, healthcare professionals can operate them more efficiently. This means less time spent on training and more time focused on patient care.
Higher User Satisfaction: Devices that meet the needs and expectations of their users lead to higher satisfaction. This can result in better compliance and more positive feedback.
Key Principles of Human-Centered Design
User Involvement: Engaging with end-users throughout the design process ensures that their needs and feedback are incorporated into the final product. This can be achieved through interviews, surveys, and usability testing.
Iterative Design: Designing in iterations allows for continuous improvement. By testing and refining the device in stages, designers can address issues as they arise, leading to a more polished final product.
Contextual Understanding: Understanding the context in which a device will be used is crucial. This includes considering the environment, the tasks being performed, and the users’ physical and cognitive abilities.
Practical Guidance for Start-Ups: Incorporating Human Factors Early
For start-ups entering the medical device market, integrating human factors early in the design process is not just beneficial but necessary. Here’s how and why:
- 1. Start Early, Before Design Controls: Human factors should be considered from the very beginning of the development process, even before formal design controls are in place. This means incorporating user research and human factors engineering into the initial concept phase.
Example: Consider a start-up developing a new type of wearable heart monitor. Before any design specifications are drafted, the team should engage with potential users to understand their needs, limitations, and preferences. This feedback can shape the initial design concept, ensuring it aligns with user expectations and reduces the risk of costly redesigns later on.
- 2. Regulatory Necessities: Regulatory bodies like the FDA and the European Medicines Agency (EMA) require evidence that human factors have been considered in the design of medical devices. This includes demonstrating that the device can be used safely and effectively by the intended users, under the expected conditions of use.
Example: The FDA’s guidance on human factors and usability engineering emphasizes the need for a thorough human factors validation process. This involves conducting usability tests to identify potential use errors and mitigate them through design improvements.
- 3. Traceability and Documentation: Documenting human factors activities is crucial. This traceability ensures that all decisions related to human factors are well-documented and can be reviewed during regulatory submissions. It demonstrates a commitment to user safety and design effectiveness.
Example: A start-up working on a new infusion pump should maintain detailed records of all user interactions, usability tests, and design iterations influenced by human factors considerations. This documentation becomes part of the Design History File (DHF) and is essential for regulatory approval.
- 4. Iterative Testing and Feedback: Implement an iterative testing approach where prototypes are tested with real users, feedback is gathered, and designs are refined accordingly. This cycle should continue throughout the development process to ensure the final product is user-friendly and safe.
Example: A company developing a new surgical tool should create multiple prototypes and conduct simulated surgeries with healthcare professionals. Feedback from these sessions should be used to make incremental improvements, addressing any usability issues identified.
Why Human Factors Needs to Be Traceable
Human factors need to be traceable to ensure that every decision made during the design process is justified and based on user needs. This traceability:
- Ensures Accountability: Every design decision can be traced back to user research or usability testing, demonstrating a clear rationale.
- Facilitates Regulatory Approval: Detailed records of human factors activities are often required by regulatory bodies to prove that the device is safe and effective for its intended use.
- Supports Continuous Improvement: Traceability allows for easy identification of past decisions and their outcomes, facilitating ongoing improvements in future designs.
Example: When developing a new drug delivery device, a start-up must document how user feedback from early usability tests influenced design changes. If a particular feature was added or modified based on user input, this should be clearly recorded and traceable through the development documentation. This traceability not only helps in meeting regulatory requirements but also in ensuring that the final product is truly user-centered.
Embracing Human Factors for Better Medical Devices
Incorporating human factors into medical device design is essential for creating products that are safe, efficient, and satisfying to use. By focusing on the needs and capabilities of users, designers can develop devices that not only meet regulatory standards but also enhance the overall healthcare experience.
By considering human factors, we can ensure that medical devices are designed not just for functionality but for the people who use them every day. This approach leads to safer, more effective, and more user-friendly healthcare solutions.
Incorporating human factorsis more than just a design choice; it’s a commitment to making healthcare safer and more effective for everyone involved. As technology continues to evolve, keeping the human element at the forefront will be crucial in developing medical devices that truly make a difference.
