Hi, 

I'm a biomedical engineer with about 4+ years of medical device development experience. It's not a lot, but it's enough to have experienced something like this. When I graduated college, I began working for a laparoscopic surgical device company. I worked on two projects that essentially failed design verification or some portion of it. The first project ended up being abandoned due to poor component selection within the design that was ultimately exposed during design verification testing.

The second project didn't really fail design verification testing, but the product launch was delayed significantly because we wanted to make sure we met design verification completion deadlines.

The delay was due to the use of components that initially failed our incoming inspections. We tried to make it work by essentially "machining" the flaw away (quite literally, I designed some of the mills and fixtures used to eliminate the flaw). This got us past verifications but stalled us afterward because we couldn't scale the "machined" modifications up high enough for the quantities we desired. 

The delay ended up resulting in a total redesign. Partly influenced by new data we came across from competitors in the market and from animal trials with surgeons.

In a way the failure lead us to a better design in a round-a-bout way

Your example certainly highlights how verification failures often shed light on component selection and manufacturability issues rather than about the test itself. This certainly illustrates how the first time designs are truly tested against real-world constraints happens during verification. Thus, weaknesses identified and their consequent root cause investigations are usually initiated at this phase, and should be pushed further than simply the surface of test results to analyzing design transfers and inspection criteria. Such investigation often takes an ample amount of time due to the fact that it involves cross-functional teams, which can also explain why delays can take seed here that push back timelines from weeks to months. 

I also agree that redesigns can ultimately lead to a better product. While conducting redesigns, they may feel laborious and costly, but they may ultimately minimize longitudinal risk by bolstering reliability, market competitiveness, and scalability. On this note, are there ways teams can anticipate manufacturability and scalability issues earlier in the design phases to make verification more of a confirmatory step?

The only industry example I have is in a biotechnology company, but with medical device development, I have an example for when I worked on creating a medical device prototype for my undergrad senior project with my group. With the prototype being built slowly for two semesters, verification testing was a part of the design process to ensure specifications are passed for the design inputs. There were about eight verification tests to do and it takes time while building the prototype. For example, a verification test to see if an air bladder can elevate up to 30 degrees and support a load of 450 pounds is being tested. This was to help move heavier patients. With the verification test, when a load of 40 pounds was applied, the test failed to elevate up to 30 degrees. This shows that the verification test failed to support a load of 40 pounds, let alone 450 pounds. When verification testing fails, that makes the design specifications fail for the design input. This shows that angle of elevation failed after each weight increment and the air bladder failed to support a weight of 40 pounds even when the acceptance criteria called for 100 pounds distributed weight loading after each weight increment. Due to this failure, it heavily affects the project and performance as that is one of the main aspects of the prototype. It causes huge delays that can extend for months due to finding a better alternative product or air bladder to support the verification test in this case. It took months to find the root cause being the actual air bladder itself and finding a better alternative with a strict deadline of two semesters. At the same time, in the real world, this would delay the project launch significantly because due to this, my group was unable to fix the problem on time for a good prototype. We were also on a strict budget and ordering material took a lot of time with other groups in the mix. Yes, many issues happen due to mechanical testing from design transfer to the prototype to the final design. It is like the vision for the project is not being communicated properly or designed properly.

This is a fun one! I work as a process dev engineer in manufacturing and my company heavily manufactures medical devices. Often there's no way to really anticipate scrap turnout and issues. What helps is if we've manufactured similar devices before; we'll use this info when charging the customer. This is the best we can do to anticipate the build. How it actually looks though is a different story and dependent on a lot of factors. Is this a new technology we've never tried before? Do we have an SME (subject matter expert) for it? And more. Additionally, companies often design their products without actual manufacturability in mind. So their design doesn't work. This should be weeded out in the prototyping stage but sometimes small issues make it through by the time it gets to process development. These delays can easily add weeks to a timeline. But due to the manufacturing environment, we often tend to push the product out in shorter term. Meanwhile the customer may add additional builds as they work on new revisions to refine their device. All these refinements can easily add years to a project.

Even with a lack of total industry experience, based on what I've observed in biomedical engineering projects, verification failures occur generally due to minor design or communication related issues which are typically not apparent until testing is more representative of real-world conditions. Design transfers seem particularly difficult as tolerancing or manufacturing specifics may change from prototyping to final production. This can result in significant delay time for design or test revisions. Designers and manufacturers could potentially prevent some of the problems associated with verification by improving their communication during the initial stages of the project. Therefore, they can identify and correct potential issues prior to the occurrence of failure rather than after it occurs.

Reading everyone’s responses, one thing that stands out is how verification failures often expose issues beyond just the test itself. Whether it’s component selection, manufacturability, tolerancing, or scalability, verification seems to be the point where design assumptions are finally stress-tested against reality. I find it interesting that many delays stem not from poor testing, but from gaps in design transfer or communication between engineering and manufacturing teams.

What also stands out is how failure can ultimately improve the product. While redesigns may feel costly and frustrating in the short term, they often reduce long-term risk and prevent larger downstream issues. From a project management perspective, this reinforces the importance of early cross-functional involvement and designing with manufacturability in mind.

I’m curious how teams can better integrate process development and manufacturing feedback earlier in the design phase so that verification becomes more confirmatory rather than corrective?

While I don’t have any formal industry experience, I do have experience following the design control process for my undergraduate capstone process. Over the course of one year, my team was developing a prototype of the arm that could train physical therapists how to perform ligament integrity tests. One of the design inputs that my team decided on was that the material used to replicate muscles should have similar material properties to human muscles. Originally, we decided to model the muscles like pneumatic muscles, using a balloon wrapped in a nylon mesh, however after performing verification testing on the samples we made in the Instron, the stiffness was way too high to meet the design specification. This was a major setback after spending a couple of weeks on the original muscle prototype. Because we had derived our specification range from peer-reviewed literature on the mechanical properties of human muscle, we knew the issue was not with the requirement itself but with our design solution. We could not change the design specification and had to find a different material to replicate muscles. Failing the test caused almost a month delay in our project, as we could not move on to assembling the full prototype until we passed verification for that component. It took extra time to research potential materials that could be used, wait for them to be delivered, and perform the verification test again. This example is much less extreme than what would happen in an industry setting. In our case, the consequence for failing the test was a project timeline delay and added stress, but in industry, a failed verification test could trigger a formal root cause investigation, negatively impact project timelines, and delay regulatory submissions.

Verification failure can be one of the most stressful phases of a project because it exposes gaps between the intended design and real world performance. From a project management perspective, I think formal tools like 5 Whys, fishbone diagrams, and controlled retesting under replicated failure conditions are critical. Clear documentation during design transfer is also huge, especially around tolerances and supplier communication as you mentioned. In terms of delays, minor verification failures can add weeks, but supplier redesigns or tooling changes can easily push timelines out several months. The key is building contingency into the schedule