=== Control thinking ===
In 1990 psychologist James T. Reason proposed the Swiss Cheese metaphor as an accident causation model. Reason hypothesized that hazards are prevented from causing losses by a series of controls, known as controls in the bowtie method. He states that these controls however are never 100% effective. Each control has unintended (inconstant) weaknesses and when these so called ‘holes’ line up a hazard can be released. According to Reason the common causes of the weaknesses in controls can often be found in the organisation (latent failures). E.g. cost & time cutting on maintenance management can eventually lead to the deterioration of the integrity of many hardware controls within a system. In the Bowtie method these weaknesses are defined as Escalation Factors and are important features to fight the illusion of control that organisations sometime tend to have.