Medical Device Manufacturing Flaws: 11 Signs You Might Be Missing

Any medical device operations executive worth their salt monitors production throughput, efficiency, yield, downtime, nonconformance, and a host of other metrics. But there are sneaky indicators that something might be going wrong with production that you might be missing.

Here are 11 not-so-obvious signs that your production processes may not be working as well as they should, based on the experience of Integrated Project Management Company’s medical device manufacturing experts.

1. An Unexpected Increase in Yield

While improving yield is always a goal, a sudden spike can sometimes be a red flag rather than a win. It might suggest defective products are slipping through undetected. For instance, visual inspection typically catches only about 80 or 85 percent of defects. So, if yield jumps unexpectedly, it’s worth asking what changed. Has there been a shift in who’s doing the inspections, or was the inspection sample size reduced? Could increased overtime be causing fatigue? Or maybe something environmental, like lighting, is affecting focus and accuracy. Taking a closer look at these factors can help ensure higher yield truly reflects better quality, not overlooked issues.

2. Consistent Overtime

If you’re scheduling overtime consistently, something is systemically off or wrong in your facility. Unexpected demand that requires overtime can sometimes be a blip on the radar. But consistent overtime could indicate staff are overworked, underexperienced, or becoming apathetic. It could also signal issues like inefficient processes or line layout, poor production scheduling, or skipped preventive maintenance.

3. Lower Maintenance Spending

A trending decrease in maintenance spending might seem like a cost-saving win. But it could also mean that the plant is neglecting routine preventive maintenance. Fewer technicians, less-frequent maintenance, and stretching the life of machinery, tooling, and components may not cause issues right away. But they will lead to greater downtime and slower speeds, and thus reduced output.

4. Minor Equipment Adjustments

If equipment needs constant tweaking or small adjustments during production, even if it just means short stops that don’t show up in downtime reports, it indicates a problem. Perhaps something gets misaligned or jammed and it only needs a nudge or a few seconds of attention. These minor issues, when you add them up, can significantly decrease throughput and erode precision. If an operator says they’re having to tweak something all day, there is a calibration problem. (And it’s frustrating for the person who has to keep on top of it.) Ultimately, this kind of recurring intervention is a signal the process isn’t running as smoothly as it should and deserves closer attention.

5. Product Variations Within Control Limits

Even when products fall within the acceptable upper and lower quality control specs, the magnitude of the variations can be a warning sign that the production process is not truly under control. Variations, while still “acceptable,” can impact user experience and lead to an increase in defects over time, even if the product is still technically sellable.

6. Unexpected Decline in Nonconformance Reports

While getting fewer nonconformance reports (NCRs) is typically a positive sign, a sudden or unexpected decline could actually indicate a problem. It could point to underreporting, complacency, fear of surfacing issues, or weakness in the quality culture. A sudden drop in reported issues can be more concerning than steady low-level findings.

7. Declining Employee Ideas

Similarly, if the number of improvement suggestions from frontline workers drops, it could mean your continuous improvement programs are going well and you have a healthy quality culture. Or it could indicate that employees feel disengaged or discouraged from recommending ideas. This can also hide operational inefficiencies, as workers closest to the process often notice issues before management does.

8. Repeated Redesign of Organizational Tools

If a manufacturing facility has to frequently redesign organizational tools like shadow boards or 5S boards, it suggests poor change management, ineffective implementation, and overall lack of leadership. When tools are introduced but not regularly reinforced, workers perceive those tools aren’t important. This doesn’t point to any one production problem, but it does indicate manufacturing won’t get the benefit of the principles and tools.

9. Documentation Backlogs

If NCRs, change orders, or device history records are piling up, it’s a sign production is moving faster than quality review can keep up. It points to systemic alignment issues between operations and quality and can create additional issues, like warehousing nonconforming product, WIP, and finished device inventory, which will delay shipping and time-to-market.

10. Shifts in Cleanroom Performance Metrics

Environmental monitoring may not show up on KPI dashboards. But unexpected increases in particle counts, air changes, or humidity deviations can signal issues in cleanroom control. If adhesives are used in production, fluctuation in humidity can be a real problem. If device assembly and packaging depend on validated environmental conditions, increased particulate counts will lead to lower yields. Monitor these metrics to ensure the health of the production environment.

11. Certification Delays

If operators are struggling to pass training modules or need repeated attempts to get certified on a process, it suggests unclear SOPs, poor training design, or creeping complexity in processes. This can be an early signal that people won’t execute consistently—a big regulatory risk.