Safety On Tap

A sunk cost is the bias in many animals, humans and pigeons included, to continue with a course of action or commitment on the basis of costs already incurred.  These costs might be time, money, energy, or even social capital (being seen to be committed).  The more we perceive that we have invested, the more likely we will continue down the same path even in the face of contrary information, changing circumstances or diminishing chances of success.