Avoiding the Sunk Costs Fallacy: Making Rational Decisions

The Sunk Cost Fallacy encapsulates a common psychological trap that many of us fall into: the inclination to persist in an endeavor simply because we have already invested significant time, effort, or money. This tendency often emerges from societal norms that celebrate persistence and resilience; we’re taught that giving up is not an option and that success requires unwavering commitment. However, this mindset can lead us down a perilous path where we find ourselves clinging to failing projects or decisions, pouring additional resources into them despite clear evidence that moving on may be more beneficial. We become akin to sailors trapped on a sinking ship, convinced that further investment will somehow salvage our initial contributions.

Yet honoring sunk costs—those investments we cannot recover—is fundamentally irrational. It blinds us to the realities of our current situation and hampers our ability to make sound future choices. Recognizing when it’s time to step back and reevaluate is crucial for personal growth and decision-making efficacy.

As difficult as it may be to acknowledge past mistakes or losses, embracing the wisdom of letting go allows us the opportunity to redirect our energy toward more promising ventures. In understanding this cognitive bias, we empower ourselves not only to overcome emotional hurdles but also to cultivate a mindset rooted in rationality and forward-thinking—a vital skill in navigating both personal endeavors and broader life challenges.

An Example of Sunk Costs Fallacy

An example of sunk cost reasoning is when we do something we won’t enjoy because we already spent the money for it. Let’s say you bought a couple tickets to a concert because the opening warm-up band has a guitar player you knew from college. You are excited to see the his band perform even though you don’t care much for the main act. The day of the concert you are notified that the warm-up band cancelled and will be replaced by a different small group you don’t care to watch. You decide to go to the concert anyway because you already purchased the tickets and don’t want to waist your money.

Logically, the money has already been spent (sunk costs) whether you go to the concert or not. A logical decision shouldn’t include consideration of the sunk cost but rather, whether going to the concert is more enjoyable than other things you could do with your evening.

Investments and Sunk Costs Fallacy

Irrational sunk cost thinking particularly interferes with investment choices. Consider owning an unusually large number of stocks in a particular company. The investment was risky but based on speculation that the company would develop a break through treatment for cancer.

The research fails and the stock tanks. Sunk cost thinking keeps the stocks, hoping for a recovery, even though they would never consider buying the stock at this point, investing in a different stock with a brighter outlook. In economic terms, sunk costs are costs that have already been incurred and cannot be recovered. The sunk cost fallacy means that we are making irrational decisions because we are factoring in the costs already incurred.

Loss Aversion and Sunk Costs Fallacy

Dan Ariely, a professor of psychology and behavioral economics at Duke University wrote that, “Our aversion to loss is a strong emotion, one that sometimes causes us to make bad decisions” (Ariely, 2010). The sunk cost fallacy may occur in part because of this emotional reaction to loss. Losses feel much worse than the positive impact of gains. Our decisions, then, give undeserved weight to avoiding loss.

Christopher Olivola, an assistant professor of marketing at Carnegie Mellon’s Tepper School of Business and the author of a 2018 paper on the topic published in the journal Psychological Science, believes that people possibly irrationally continue in sunk costs because they want to convince themselves that “they’ve managed to recapture the loss” (Ducharme, 2018).

Rational Choice

Rational choice theories advocate that our decision-making processes should be grounded in an analysis of future prospects rather than past investments (Murphy, 2024). This perspective posits that only the potential benefits and costs associated with current choices ought to influence our decisions, while irrecoverable expenditures—those sunk costs—should be disregarded unless they help shape expectations about future outcomes (Vasconcelos, 2020).

By adhering to this rational framework, individuals can make more informed choices that align with their long-term goals and well-being. Ignoring sunk costs allows us to approach decisions without the emotional baggage of previous commitments, fostering a mindset focused on what lies ahead rather than what has already been lost.

In contrast, the sunk-cost fallacy represents a significant deviation from rational decision-making principles. As Olivola (2018) elucidates, people often find themselves pursuing inferior alternatives simply because they have previously invested substantial resources into them. This adherence to past investments can lead to poor judgments and perpetuate cycles of unproductive behavior.

The failure to recognize when it’s time to pivot or abandon a failing endeavor results not just in wasted resources but also in missed opportunities for growth and success elsewhere. Understanding these dynamics empowers individuals to cultivate healthier decision-making habits by prioritizing prospective benefits over historical losses—a critical step toward achieving greater satisfaction and effectiveness in both personal and professional domains.

Associated Concepts

Loss Aversion: As sunk costs increase, so does the perceived potential loss associated with the task, idea, project, or commitment.
Cognitive Heuristics: These are mental shortcuts or rules of thumb that the human mind uses to simplify complex decision-making processes. These heuristics allow individuals to make quick judgments and decisions based on limited information and cognitive resources.
Miswanting: This refers to the phenomenon of desiring or pursuing things that do not contribute to one’s long-term happiness or well-being. It involves a disconnect between what an individual believes will make them happy and what actually brings them fulfillment.
Counterfactual Thinking: This refers to the cognitive process where we imagine different outcomes or events from past actions, often leading to regret or sorrow. It can serve functional purposes like guiding future decision-making, but it can also be harmful if it remains focused on unreachable, idealised alternatives.
Slippery Slope Fallacy: This fallacy predicts that one event will create a chain of negative consequences. This fallacy hinders healthy discourse and cooperation.
Arrival Fallacy: The belief that reaching a goal will make us happy, even if the journey has been unfulfilling.
Commitment Escalation: Continuing to invest in a failing project due to prior commitments or emotional attachment.

A Few Words by Psychology Fanatic

We are not machines, only acting on cold data. Decision making is a complex process, involving emotions, ego, and other unseen forces. A cold rational “Spock” like reaction to decisions may serve well on the U.S.S. Enterprise but not in the world of human relationships. As we fumble through our decisions, we should investigate distorting biases, such as loss aversion and sunk cost fallacy, and make corrections. However, occasionally, emotions provide guidance that rationality may overlook. In conclusion, we need both emotion and rationality to navigate the complex maze of life.

Last Update: January 15, 2026

References:

Ariely, Dan (2010). Predictably Irrational, Revised and Expanded Edition: The Hidden Forces That Shape Our Decisions. Harper Perennial; Revised and Expanded ed. edition. ISBN 10: 0061353248
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Ducharme, J. (2018). The Sunk Cost Fallacy Is Ruining Your Decisions. Here’s How. Time. Published: 7-26-2018; Accessed: 8-26-2021. Website: https://time.com/5347133/sunk-cost-fallacy-decisions/
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Murphy, T. Franklin (2024). How Rational Choice Theory Influences Human Behavior and Decision Making. Psychology Fanatic. Published 12-2-2024; Accessed: 5-12-2025. Website: https://psychologyfanatic.com/rational-choice-theory/
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Olivola, C. (2018). The Interpersonal Sunk-Cost Effect. Psychological Science, 29(7), 1072-1083. DOI: 10.1177/0956797617752641
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Vasconcelos, M. (2020). The road ahead for sunk costs. Learning & Behavior, 48(1), 1-2. DOI: 10.3758/s13420-019-00375-8
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