Quality cost

Quality costs ( English Cost of Quality , abbreviated CoQ ) are costs in companies that arise from ensuring product quality or service quality , as well as the costs that arise from poor quality.

General

Quality costs are part of manufacturing costs . They were named after the term coined in the USA in the 1940s. According to this concept, quality costs are made up

• Error cost ( English failure costs )
• Prevention costs ( English prevention costs ) and
• Test costs ( English appraisal costs )

This concept is also reflected in the definitions of the German Institute for Standardization and the German Society for Quality (DGQ), which understand this as costs, "... which are primarily due to activities of error prevention, through scheduled quality checks and internal or external errors are caused ". In the language of ( ISO 55350 ):

${\displaystyle {\text{Qualitätskosten}}={{\text{Prüf- und Beurteilungskosten}}+{\text{Fehlerverhütungskosten}}+{\text{Fehlerbeseitigungskosten}}}}$

When it comes to quality-related costs, a distinction is made between conformity and deviation costs. Compliance costs are known, can be planned and cannot be avoided. Deviation costs are not known, cannot be planned and can only be estimated ( EN ISO 9004-1 ).

species

Quality costs therefore arise in error prevention (testing costs), error correction (error costs) and quality improvement. The largest proportion of these subspecies is usually attributable to the error costs.

history

Philip B. Crosby takes up the concept of quality costs as a central element of his work in the field of quality assurance. He popularized the concept at a time when quality assurance was dominated by concepts by William Edwards Deming and Joseph M. Juran . Today's distribution is largely based on Crosby's work.

DGQ concept

In its general recommendations, the DGQ also adds the costs for

• Quality management
• Quality capability studies
• Quality audits
• Training
• Test planning
• Test equipment planning / monitoring (e.g. calibration of measuring devices)
• Supplier evaluation

at the above costs.

criticism

The consideration only assesses the costs from an operational perspective. According to the concept described, only the costs of quality damage are relevant that the producing or selling company has to bear. If the person concerned, for example the driver of a car with tire damage or the crew and passengers of a sunken ship, incurs additional costs or consequences, these are not included in the analysis. Some of these considerations can be found in product lifecycle management . Others must be viewed from an ethical point of view.

Individual evidence

1. ^ ^{A b} Tilo Pfeifer, Quality Management - Strategies - Methods - Techniques , Carl Hanser Verlag, Munich / Vienna, 1993, p. 383 ff., ISBN 3-446-16526-6
2. ↑ Gabriel Schneider / Ingrid Katharina Geiger / Johannes Scheuring, Process and Quality Management , 2008, p. 117
3. ↑ Jochem Piontek, Controlling , 2005, p. 192
4. ^ Philip B. Crosby, Quality is free: the art of making quality certain , New York; McGraw-Hill, 1979, ISBN 0-07-014512-1