Schrödinger’s Product: Why Testing Defines Quality in Product Development and Manufacturing

January 16, 2026

design validation, design verification, engineering testing, manufacturing quality, manufacturing readiness, product development risk, product testing, Quality Assurance, risk management, untested product risk

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A Product Is Both Good and Bad—Until Tested

Not everything can be turned into a process. This is especially true early in product development, where ideas evolve faster than data. But there is a dangerous phase where uncertainty masquerades as progress. Like Schrödinger’s famous thought experiment, an untested product exists in a paradoxical state: it is simultaneously good and bad until measurement collapses the uncertainty. The image captures a reality that engineers and manufacturers know well—untested product risk persists until evidence replaces belief.

Untested Product Risk in Product Development

In product development, confidence often grows faster than proof. Designs pass reviews, simulations look promising, and teams move forward assuming success. Without testing, however, those assumptions remain unverified. For our part, we prefer to seek evidence to disprove what we think. The minute we can refute what we think, we know we are at least in part incorrect. Finding evidence that supports what we believe still doesn’t mean we’re correct. We must guard against confirmation bias. Also, to be sure, there is no guarantee that our product development efforts, including simulations and testing, find every failure mode.

Assumptions Are Not Evidence

Before testing, the product development team’s contingent often makes assumptions. Who am I kidding? Everybody on the team makes assumptions, some of which are likely valid, some – not so much.

Performance will meet requirements
Tolerances are sufficient
Failure modes are understood
Manufacturing variability is manageable

Until tested, none of these are facts. Untested product risk grows when schedules reward forward motion more than learning. The longer testing is delayed, the more expensive uncertainty becomes. Also, this does not mean testing should be limited to testing requirements; in fact, that is not the way to success, according to experience. In fact, we have written and spoken on this for years, including this article in IEEE Reliability Magazine.

Manufacturing Inherits Untested Product Risk

When a product reaches manufacturing without sufficient validation, the factory becomes the test environment—an expensive and unforgiving one.

Why Manufacturing “Discovers” Problems

Manufacturing reveals reality:

Parts must fit every time, not just once
Processes expose sensitivity to variation
Operators uncover undocumented assumptions
Quality systems detect what development missed

At this point, untested product risk converts directly into scrap, rework, line stoppages, and customer dissatisfaction. Manufacturing is often blamed for issues that originated upstream in unvalidated design decisions.

Testing Collapses Uncertainty

Testing is not about proving success; it is about discovering truth. Just as observation determines Schrödinger’s cat’s state, testing determines whether a product truly meets its intent, and the ability of the product to work in the expected environment that may include unexpected stimuli from either the environment or customer use.

What Effective Testing Provides

Our calculations, drawings, and simulations tell us some things about the product, but not everything.

Confirmation of design margins
Visibility into failure modes
Evidence-based tolerance validation
Confidence in manufacturing readiness

Without testing, quality is theoretical. With testing, quality becomes measurable.

Managing Untested Product Risk Across the Lifecycle

Reducing untested product risk requires intentional discipline across both product development and manufacturing.

In Product Development

In product development, we test to ensure the product is maturing toward the desired end result, allowing corrective actions along the way rather than a surprise at delivery.

Treat testing as a risk-reduction activity, not a milestone
Testing is integrated closely with design incarnations as the design matures
Test early to expose assumptions
Use results to refine requirements and tolerances – or alter the design
Document what is known versus believed

In Manufacturing

We test whether our theoretical manufacturing processes and tools actually achieve the desired throughput and first-pass yield. Testing will feed out control plans, what things are critical to the quality, and how we will measure and control them.

Require evidence of validation before release
Resist compensating for untested designs with informal controls
Feed test results back into design standards

Testing aligns belief with reality and prevents uncertainty from silently propagating.

Quality Is Undefined Until Proven

Before testing, a product is neither good nor bad—it is unknown. The longer organizations tolerate this ambiguity, the greater the cost when reality finally asserts itself. Managing untested product risk is not about slowing innovation; it is about ensuring that learning happens when change is still affordable.

Test early. Test intentionally. Collapse uncertainty before it collapses your schedule, cost, or credibility.