This is a Lexicon entry: the mechanism, when it shows up, and the countermeasure. The full correction, with real-world cases and the audit prompt, hasn't been written yet.
Definition
The tendency to keep inefficient systems or habits simply because they have become the accepted norm. The QWERTY keyboard was designed to slow typists down and prevent typewriter jams - yet here we still are.
When it shows up
Established technologies, organisational processes, cultural practices. Questions like 'why do we do it this way?' where the answer is 'historical accident'.
Failure mode
Systems lock into configurations chosen early for reasons no longer relevant. QWERTY was for mechanical typewriters; we use it on phones. Switching costs accumulate faster than pressure to switch so inefficient arrangements persist.
Countermeasure
Distinguish historical path from current optimum. When designing new systems, assume path dependence will lock in your choices. When stuck in old systems, measure switch cost versus ongoing friction before assuming change is too expensive.
Related traps
Also connected in the map5 more, locked
Credit & first seen
DiscoveredArkes, H.R.&Blumer, C. (1985).'The psychology of sunk cost.'Organisational Behaviour and Human Decision Processes 35(1), 124-140 source ↗
Also revealed
Entry #72 of 631 in The Lexicon · see the full Lexicon