The ETTO Principle Quotes

“In accident investigation, as in most other human endeavours, we fall prey to the What-You-Look-For-Is-What-You-Find or WYLFIWYF principle. This is a simple recognition of the fact that assumptions about what we are going to see (What-You-Look-For), to a large extent will determine what we actually find (What-You-Find). (The principle is furthermore not limited to accident investigation, but applies to human perception and cognition in general.) In accident investigations, the guiding assumptions are sometimes explicit, for instance when they are given as a directive or objective.

Erik Hollnagel. The ETTO Principle: Efficiency-Thoroughness Trade-Off (Kindle Locations 998-1000). Kindle Edition.”
― Erik Hollnagel, The ETTO Principle: Efficiency-Thoroughness Trade-Off

“Yet by assigning blame or pointing to specific causes we disregard the fact that the whole system only worked because everyone made approximate adjustments to their work.”
― Erik Hollnagel, The ETTO Principle: Efficiency-Thoroughness Trade-Off: Why Things That Go Right Sometimes Go Wrong