How Complex Systems Fail

How Complex Systems Fail

Richard I. Cook · 1998 · (View Paper → )

This paper provides crucial insights into the failure mechanisms of complex systems. The work is foundational in safety critical fields like healthcare, aviation, and technology.

1. Complex systems are intrinsically hazardous systems.
2. Complex systems are heavily and successfully defended against failure.
3. Catastrophe requires multiple failures – single point failures are not enough.
4. Complex systems contain changing mixtures of failures latent within them.
5. Complex systems run in degraded mode.
6. Catastrophe is always just around the corner.
7. Post-accident attribution accident to a ‘root cause’ is fundamentally wrong.
8. Hindsight biases post-accident assessments of human performance.
9. Human operators have dual roles: as producers & as defenders against failure.
10. All practitioner actions are gambles.
11. Actions at the sharp end resolve all ambiguity.
12. Human practitioners are the adaptable element of complex systems.
13. Human expertise in complex systems is constantly changing.
14. Change introduces new forms of failure.
15. Views of ‘cause’ limit the effectiveness of defences against future events.
16. Safety is a characteristic of systems and not of their components.
17. People continuously create safety.
18. Failure free operations require experience with failure.