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.
When it shows up
Marketing (the "sold out" premium option makes the next-best option look more attractive). Real estate (showing a house that's just gone under contract shifts preference toward a similar available listing). Menu design (a temporarily unavailable dish redirects attention to adjacent items).
Failure mode
Preferences shift based on irrelevant alternatives. Choices become context-dependent in ways the chooser doesn't recognise. Marketers and negotiators exploit this by introducing phantom options that were never intended to be selected.
Countermeasure
Evaluate each option on its own merits, independent of unavailable alternatives. Ask: "Would I still prefer this option if the unavailable one had never been mentioned?" Apply CL-1 (Pause Protocol).
Related traps
Also connected in the map3 more, locked
Also revealed
Entry #73 of 631 in The Lexicon · see the full Lexicon