" We chose the quality because the luck had become too expensive. " (Jean Abraham) " In the running in the quality, there is no finishing line. " (David Kearns) " The quality is never an accident; it is always the result of an intelligent effort. " (John Ruskin)

The cause of failure is the circumstance (or event) at the origin of the failure and related to the installation. It is not possible, at the time of this phase, to obtain an exhaustive list of the causes of failure. An effective technique consists in using a working tool of well-known group: the diagram of Ishikawa or "fish-bone". One carries out a diagram by mode of failure and one seeks to group on this diagram the interdependent causes in a ramified way.  Another analysis consists in using lists of analysis of the risk, non-exhaustive, being used as memory assistance to the person in charge to review the known causes of dysfunction.