A sunk cost fallacy occurs when we feel we have invested too much to quit. This psychological trap pushes us to stick with a plan even if it no longer serves us and the costs clearly outweigh the benefits.
We can come to validate hypotheses when the results do not directly validate them.
Or continuing to want to validate a hypothesis because you have spent too much time on it.
Or to continue a methodology sow ambush because you spent time there
Cause
The sunk cost fallacy leads people to believe that past investments (i.e. sunk costs) justify new investments and commitments. They believe this because the resources already invested will be lost. In rational decision-making, sunk costs should play no role in our future actions because we can never recoup the money, time, or energy we have invested, regardless of the result.
Instead of considering present and future costs and benefits, we obsess over our past investments and let them guide our decisions. It is an error or faulty reasoning (such as the red herring fallacy or the ecological fallacy) that creates a vicious cycle of bad investments, also known as "throwing money away." ".
The sunk cost fallacy occurs because we are not always rational decision makers. Rather, we are often influenced by our emotions, which bind us to our prior commitments, even in the face of evidence that doing so is not in our best interest.
The following factors may help explain why the sunk cost fallacy occurs:
- Loss aversion. Because losses tend to be much worse than gains, we are more likely to try to avoid losses than to seek gains. The more time and other resources you devote to something, the more loss you will feel by walking away.
- Framing effect. Our perception of a situation or option depends on whether it is presented in a negative or positive light. In combination with loss aversion, according to the sunk cost fallacy, we believe that abandoning a project amounts to a loss (negative frame), even though it is perfectly rational to stop wasting our resources on something which does not work. Rather, monitoring allows us to consider our decision as a success (positive framework).
- A desire to avoid waste. One of the reasons we fall into the sunk cost trap is that stopping would mean admitting that all the resources we have invested up to that point have been wasted. Waste is clearly not a desirable quality. This explains, for example, why we try to finish reading a book we don't like: if we stop, we feel like the time we've spent reading so far is wasted.
- Optimism bias. This means we overestimate the chances that our efforts will ultimately pay off, leading us to ignore any warning signs. As a result, we continue to devote money, time or energy to projects because we are convinced that it will all pay off in the end.
- Personal responsibility. The sunk cost fallacy affects us most when we feel responsible for a decision and the sunk costs that accompany it. This creates an emotional bias that causes us to cling to the project, decision, or course of action for which we feel personally responsible.
An interpersonal bias
In a series of experiments, the researchers wanted to find out whether people also felt guilty about wasting other people's resources.
In one experiment, participants were asked to imagine that they were attending a potluck party and that after eating a few bites of a rich cake, they felt full. Some were told the cake was purchased from a local bakery on sale, while others were told the cake was expensive and came from a store an hour's drive away.
In each scenario, participants were asked to imagine that they had bought the cake themselves or that someone else had brought it to the potluck. They were then asked if they would finish the cake even if they felt full.
According to the results, people who were told they would eat the expensive cake were significantly more likely to say they would continue eating. Interestingly, this had nothing to do with who bought it: friends, strangers, or the participants themselves.
These results show that the sunk cost fallacy also has an interpersonal dimension (i.e., people will modify their choices to honor the investments of others and not just their own).
How to Avoid the Sunk Cost Fallacy
It can be difficult to overcome the sunk cost fallacy, but the following strategies can help:
Be careful with your reasoning. Are you prioritizing future costs and benefits, or are you hostage to your previous investment or commitment, even if it no longer serves you? Do you consider new data or evidence in your decision to continue or abandon a project?
Consider the “opportunity cost.” If you continue to invest in a project or relationship, what are you missing? Is there another path that could bring you more benefit or fulfillment?
Avoid the emotional investment trap. When you feel emotionally invested in a project, you risk losing sight of what's really happening. This is when the sunk cost fallacy comes into play and sends you down the wrong path. Seeking advice from people who are not emotionally involved can open your eyes and help you make an informed decision.
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