Escalation of commitment
Sticking with, and investing more in, a failing decision because we have already backed it, especially when we are personally responsible for it.
Escalation of commitment is the tendency to keep backing a decision, and even to put more into it, after evidence shows it is going wrong, because we have already committed ourselves to it.
An everyday example: carrying on with a repair on an old car because you have 'already spent so much on it', instead of asking whether the next payment is worth it on its own.
In a classic 1976 study, the psychologist Barry Staw asked 240 business students to play a company's finance officer. Students who had personally chosen a division that then did badly gave it the most new money in a second round, an average of about 13 million of a 20 million dollar budget.
It is not simply stubbornness, and not every study finds it: later replications have given mixed results. Personal responsibility and a public stake, like a pamphlet with your name on it, seem to make it stronger.
