Quality characteristics

Deliver value with the right quality at speed. That’s what organizations ask of their IT-teams. To determine the right quality the teams use the quality characteristics. These are a very useful tool to identify various characteristics of quality that are important for the stakeholders of an IT-system.

Functional testing usually takes up most of the effort and time spent on testing. Often however, the non-functional testing gets less attention than it should, because many IT-failures relate to non-functional problems. [more info: functional and non-functional testing]

Note: In 2023 the International Standards Organization has published a new version of the ISO25010 standard. The TMAP team is currently studying the updates and it is expected that in the 4th edition of the TMAP book “Quality for DevOps teams” the new standard will be discussed and then also this website and the concerning training course(s) will be updated. A first impression of the changes shows that not having the new version yet, doesn’t give large differences in daily quality engineering & testing work.

ISO 25010 quality characteristics for product quality

The quality characteristics and their subcharacteristics for product quality are:

• Functional suitability – The degree to which a product or system provides functions that meet stated and implied needs when used under specified conditions.
  Functional completeness 
  Functional correctness 
  Functional appropriateness
• Performance efficiency – The performance relative to the amount of resources used under stated condition.
  Time behavior 
  Resource utilization 
  Capacity
• Compatibility – The degree to which a product, system or component can exchange information with other products, systems or components, and/or perform its required functions, while sharing the same hardware or software environment.
  Co-existence 
  Interoperability
• Usability – The degree to which a product or system can be used by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a specified context of use. Appropriateness recognizability 
  Learnability 
  Operability 
  User error protection 
  User interface aesthetics 
  Accessibility
• Reliability – The degree to which a system, product or component performs specified functions under specified conditions for a specified period of time.
  Maturity 
  Availability 
  Fault tolerance 
  Recoverability
• Security – The degree to which a product or system protects information and data so that persons or other products or systems have the degree of data access appropriate to their types and levels of authorization.
  Confidentiality
  Integrity 
  Non-repudiation 
  Accountability 
  Authenticity
• Maintainability – The degree of effectiveness and efficiency with which a product or system can be modified by the intended maintainers.
  Modularity 
  Reusability 
  Analysability 
  Modifiability 
  Testability
• Portability – The degree of effectiveness and efficiency with which a system, product or component can be transferred from one hardware, software or other operational or usage environment to another.
  Adaptability 
  Installability 
  Replaceability

Detailed information about these characteristics and their subcharacteristics can be found in [ISO25010 2011].

ISO25010 quality characteristics for quality in use

The quality characteristics and their subcharacteristics for quality in use are:

• Effectiveness – The accuracy and completeness with which users achieve specified goals. (no subcharacteristics)
• Efficiency – The resources expended in relation to the accuracy and completeness with which users achieve goals. (no subcharacteristics)
• Satisfaction – The degree to which user needs are satisfied when a product or system is used in a specified context of use.
  Usefulness
  Trust
  Pleasure
  Comfort
• Freedom from risk – The degree to which a product or system mitigates the potential risk to economic status, human life, health, or the environment.
  Economic risk mitigation
  Health and safety risk mitigation
  Environmental risk mitigation
• Context coverage – The degree to which a product or system can be used with effectiveness, efficiency, freedom from risk and satisfaction in both specified contexts of use and in contexts beyond those initially explicitly identified.
  Context completeness
  Flexibility

Detailed information about these characteristics and their subcharacteristics can be found in [ISO25010 2011].

Sogeti has defined two extensions to the ISO25010 standard. The first extension was published in 2018 and contains 3 additional product quality characteristics related to Artificial Intelligence (AI) and robotics. The second extension was published in 2022 and contains 1 additional characteristic for quality in use about Sustainability.