Costly Signaling
if it were cheap to fake, nobody would believe it
Grounded in the research on Wikipedia: Signalling theory / Costly signaling (Zahavi's handicap principle); Michael Spence, job market signaling (1973)
[ ] what it actually is
A signal you can only send if it actually cost you something. Money, time, risk, effort. The cost is the point: anyone can SAY they're rich, fit, or loyal, but the words are free so they prove nothing. Burning real resources on a display is what makes it believable, because a faker can't afford to burn the same. The price tag is the proof.
[ ] the real science
Biologist Amotz Zahavi called it the handicap principle (1975): a peacock's absurd tail is honest precisely because a weak bird couldn't survive dragging it around. Economist Michael Spence won a Nobel for the human version (1973): a degree signals you're capable mainly because finishing it is hard. The thread is identical. Honesty is enforced by the signal being expensive, not by anyone being trustworthy.