Product durability: how to assess and improve it
Product durability is the ability of a product to maintain its intended functions and performance over time, under defined conditions of use, maintenance and repair.
Product durability goes beyond making a product physically robust. Its longevity also depends on its reliability, its ability to be maintained and repaired, the availability of spare parts and technical support, and the way these factors are considered throughout its lifecycle.
For manufacturers, understanding product durability therefore means being able to identify what limits a product’s service life, measure its performance, improve its design and provide evidence of the results achieved.
LONGTIME® supports manufacturers through this process, from initial assessment and improvement through to independent verification and certification.
What is the durability of an object?
Product durability describes a product’s ability to continue performing its intended function over time, under defined conditions of use, maintenance and repair. It should not be confused with robustness alone.
A product may be mechanically robust but difficult to repair when a component eventually fails. Conversely, a highly repairable product may still have a short service life if failures occur too frequently.
Product durability therefore needs to be considered as part of a broader product longevity strategy, combining the prevention of premature failures with the ability to maintain, repair and support the product throughout its expected service life.
Why does product durability matter?
Improving product durability can help products remain functional and in use for longer, reducing the need for premature replacement.
For manufacturers, durability is also a product-performance and business issue. It can influence product quality, customer satisfaction, after-sales costs, repair strategies and the ability to substantiate claims about reliability, repairability or longevity.
Most importantly, these claims need to be supported by objective and verifiable evidence. This shifts the question from “Can we say that our product is durable?” to “What evidence can we provide to demonstrate its durability?”.
What determines the durability of a product?
There is no single characteristic that makes a product durable. Long-term performance depends on several complementary factors, including reliability, repairability, maintainability and the support available throughout the product’s service life.
Reliability
Product reliability is the ability of a product to perform its required function under defined conditions for a given period of time.
Reliability is closely linked to the prevention of premature failures. Product design, component selection, operating stresses, manufacturing quality and validation testing can all influence reliability over time.
A product designed for longevity should therefore not only work correctly when new: its critical functions and components should be designed to withstand the conditions they are expected to encounter throughout their intended use.
Repairability and maintainability
Even a highly reliable product may eventually experience wear or component failure.
Repairability determines whether the product can be restored to working condition when this happens. Accessibility, disassembly, diagnostics, replaceable components, repair information and the availability and cost of spare parts can all influence whether repair is practically possible.
Maintainability is equally important. Appropriate maintenance can help prevent failures, preserve performance and extend the product’s useful life.
Spare parts and technical support
A technically repairable product cannot necessarily remain in use if the parts, information or support required for repair are unavailable.
Long-term access to spare parts, technical documentation, diagnostic information and repair support therefore contributes to product longevity.
This is why assessing durability requires looking beyond the physical product itself and considering the ecosystem that supports it throughout its service life.
How is product durability assessed?
There is no single test capable of establishing the durability of every product. A meaningful durability assessment combines different methods according to the product, its intended use, its critical components and the failure mechanisms that may limit its service life.
1. Define the intended use and expected stresses
The first step is to understand how the product will actually be used.
This includes operating conditions, frequency of use, environmental conditions, maintenance requirements and the mechanical, electrical, thermal or other stresses to which the product may be exposed.
Without a clearly defined use scenario, durability results are difficult to interpret.
2. Identify critical functions and potential failure modes
The functions and components that can determine the end of the product’s useful life need to be identified.
Methods such as functional analysis, failure analysis, fault-tree analysis and stress analysis can help manufacturers understand where failures may occur and which components require particular attention.
3. Assess reliability
Reliability analysis and testing can then be used to evaluate whether critical components and functions can withstand expected operating conditions over time.
Depending on the product, this may involve endurance testing, cycle testing, environmental testing or other product-specific protocols.
4. Assess repairability and maintenance conditions
Durability assessment should also consider what happens when wear or failure occurs.
Can the product be diagnosed? Can it be disassembled? Can critical parts be replaced? Are repair instructions available? Are spare parts accessible over time?
These factors help determine whether a failure will result in a repair or in premature product replacement.
5. Monitor real-world performance
Laboratory testing and design analysis provide valuable evidence, but durability can also be monitored throughout the product’s lifecycle.
Failure rates, warranty data, repair records, returned products and other after-sales indicators can help manufacturers identify recurring weaknesses and continuously improve product reliability and longevity.
How well does your organisation integrate product durability into its practices?