OR in the real world: How things go wrong

Rude intrusions of the real world come in many forms and guises. Most of these intrusions are due to the perversity of the real world and the difficulty of analyzing any system that incorporates the human element. That is what Operational Research OR is all about: analyzing man/machine systems in all of its complexities. But, as Operational Research OR analysts, also should recognize that we intrude in the real world and have to consider how the practice-or rather the mispractice-of Operational Research OR causes rude intrusions in what we hope to accomplish. This paper describes what previous research has determined to be the causes of most Operational Research OR (modeling) failures, and recounts a particular study that illustrates rude intrusions. It attempts to differentiate between rude intrusions of the real world on the Operational Research OR process, and rude intrusions caused by the Operational Research OR process.