Money & WorkMental model
Winning the auction is evidence you bid too much.
When everyone estimates the same unknown value, the optimist with the highest estimate wins. That is exactly why the winning price sits systematically above the true value. Three engineers described the effect in 1971 for oil drilling rights in the Gulf of Mexico.
Useful: Before bidding, shade your estimate down deliberately – the win itself is bad news about your number.
Source: de.wikipedia.org