Sunk Cost Fallacy: Why You Stay on the Wrong Train (and How to Overcome It)

It usually starts with a sentence that sounds sensible. “I’ve already put so much into this.” I hear it in therapy rooms. I see it in survey data. I catch it in my own choices, too. If you read this, you’ll leave with three things: a name for the pattern that makes staying feel safer than leaving, the small mental flip that changes the decision, and a decision point you can actually sit with instead of circling for months.

Here’s what I’m trying to do, early and plainly. A lot of writing about the sunk cost fallacy moves too fast to the part where you’re supposed to “let go.” That skips the lived reality, the part where leaving can feel irrational even when staying is draining you. I want to stay with the mechanism longer, the way it shows up in real choices, and then offer a few ways I’ve seen people loosen it without pretending the decision is simple.

Core question:
Am I staying because this is right, or because I’ve already paid so much to be here?

What is the sunk cost fallacy?

The sunk cost fallacy is the pull to continue a commitment because you’ve already invested time, money, effort, or emotion, even when continuing no longer serves you.

That’s close to what Hal Arkes and Catherine Blumer described in 1985, just brought into the kinds of decisions people actually arriveath. Past investment starts acting like evidence. Even when it doesn’t improve, what happens next?

In plain language, it is when your past becomes the reason you sacrifice your future.

Main takeaway, the one I return to when I get stuck myself: those costs are fixed. They do not become more recoverable because you keep paying.

Why the sunk cost fallacy keeps you on the wrong train

The brain is not doing something stupid here. It’s doing something protective, or it thinks it is.

I’ll watch someone describe a job that is slowly flattening them. They dread Mondays. Their sleep is off. They can list ten ways it isn’t a fit anymore. Then they say, quietly, “But I’ve already been here six years.” It lands like a conclusion. Like a rule.

This is the “wrong train” feeling. Not because the original choice was bad. People change. Context changes. The fit changes. The investment stays. Heavy. Leaving starts to feel like admitting the last few years were pointless.

Wendy Rose Gould updated a Verywell Mind piece on this on December 23, 2025, and it was reviewed by David Susman, PhD. The article describes the familiar rationalization: since the cost can’t be recovered, you might as well stay the course and allocate more resources to improve the situation. Then you stay in an unfulfilling, stagnant situation and lose more of what matters: emotional energy, time, sometimes money.

There’s a specific NIH example I’ve used with trainees because it sounds like real life, not a textbook. Amanda Dumsch wrote on the NIH OITE careers blog on November 22, 2021, about people saying, “I was a pre-med major,r so I must go to medical school,” or “I’ve researched this topic for five years, I can’t stop now.” It’s not that they lack intelligence. Commitment, identity, and emotion keep pulling the decision back toward the past.

Sometimes I wonder if we over-label this. Not every hard season is a fallacy. Still, the pattern repeats in ways that are hard to ignore.

What sunk cost fallacy sounds like in real life.e

It often shows up in thoughts that feel responsible, loyal, or “strong,” such as:

• “I’ve already spent years on this.”
• “It would be a waste to leave now.”
• “I can’t start over.”
• “I’ve come too far to quit.”

And it tends to attach itself to the very areas where identity and emotion are involved:

• The relationship that once felt like home but now drains us.
• The job we prayed for that slowly erodes our joy.
• The life path that once seemed right but now feels misaligned.

I’ve noticed something els,e too. People don’t usually say, “I’m afraid.” They say, “It would be a waste.” Waste sounds rational. Fear sounds exposed. The sunk cost fallacy gives fear a respectable outfit.

But what if the discomfort is the sign? What if stuckness is your mind trying to protect you from a loss that already happened, and in doing so, it keeps extending the loss into the future?

Where the sunk cost fallacy shows up in everyday decisions

People think of the sunk cost fallacy as money. But it shows up anywhere there is investment.

Some specific examples might include:

• Finishing a book or movie you dislike just because you’ve started it
• Gambling more money to try to make up for lost bets
• Investing additional energy and time into a friendship that’s one-sided and proven unlikely to change course
• Remaining in a chosen education track even though you know it’s not what you want to do anymore
• Staying in a romantic relationship where values are misaligned and needs aren’t being met, because you’ve been together for so long already. 
• Sticking to a hobby you dislike because you’ve already spent the money on supplies
• Remaining at a job or on a career track that’s no longer serving you or your future. re
• Throwing additional money at an investment/product/item in hopes of a better return when you’ve already lost money and things aren’t likely to improve.

Even large entities, governments, companies, and sports teams, fall for it. They keep allocating resources to projects, products, strategies, or programs that are not profitable or successful.

One detail from Gould’s 2025 update that I keep coming back to is this: studies have shown that the larger the loss, the higher the sunk-cost bias. The bigger the investment, the less likely you are to shift gears and walk away. That fits what Veronika Tait and Harold L. Miller Jr. explored in 2019 when they looked at loss aversion and investment amount as a factor.

This is where people get mislabeled as “indecisive.” Sometimes it’s not indecision. It’s a brain trying to avoid the feeling of wasted effort.

Why this bias feels so powerful (and so personal)

Sunk cost thinking rarely travels alone. Two other effects often intensify it.

Loss aversion (Kahneman and Tversky, 1979)

Kahneman and Tversky’s prospect theory work in 1979 is the one most people bump into without knowing the name. Losses hit harder than gains. The mind reacts more intensely to losing something than to gaining the same amount.

In the 2025 Verywell Mind update, psychiatrist Yalda Safai, MD, MPH, described it in a way that sounds like a session note: the impact of loss feels worse than the prospect of gain, so we keep making decisions based on past costs instead of future costs and benefits.

That’s why leaving can feel more painful than staying, even when staying costs you every day.

Status quo bias (Samuelson and Zeckhauser, 1988)

Samuelson and Zeckhauser’s work in 1988 on status quo bias is another amplifier. The current state gets extra weight because it’s the current state.

So people stay. Not because it’s good. Because it’s familiar.

Put these together, and you get the lived experience version:

• We fear the unknown more than continued pain.
• We’ve invested so much time, effort, and emotion.
• We confuse quitting with failure.
• We wait for external signs louder than our own knowing.

Sometimes I’m not sure which part is strongest in any given decision: fear of loss, comfort of familiarity, or self-judgment about “quitting.” It varies. The mix is what traps people.

Signs you’re stuck in sunk cost thinking

Sometimes what looks like “being practical” is actually sunk cost logic.

Watch for these patterns:

• You defend the past more than you discuss the future.
• Your reasons to stay are mostly history-based, not values-based.
• You feel chronic exhaustion or burnout.
• You dread something you once loved.
• You feel emotionally numb or resentful.
• You carry constant self-doubt or anxiety.
• You hear a quiet, persistent voice saying, “This isn’t it.”

I’ve also seen the subtle version. People get very logical. They build arguments. They can talk for an hour about what they’ve already put in, and barely talk about what they want next.

That imbalance is information.

How to know when to walk away (without panicking or self-betraying)

There’s a fine line between knowing when to stay the course and when to walk away.

For example, you might go through a totally normal rough patch in a relationship, and that isn’t necessarily grounds for leaving. Or you might try a hobby you’re not 100% excited about, and end up loving it once you get past the awkward “I’m not very good at this” hurdle.

This is where I get cautious. I don’t love advice that turns every discomfort into “leave.” Some people do need to stay and repair. Some projects get better after the boring middle. Some relationships mature after a hard season.

But if past results haven’t paid off, it’s more likely they won’t in the future either. That’s basically Safai’s point in the 2025 article. She put it plainly: the best predictor of the future or future behavior is the past. If up to this point the relationship, hobby, friendship, job, and so on haven’t served you in any positive regard, it likely won’t in the future.

Also, consider the following:

• Poor outcomes: If you’re repeatedly met with an unfulfilling outcome despite best efforts, re-evaluate.
• Opportunity cost: Where will your dollar/energy/time get the most value? Can you get more return on your resources by venturing elsewhere or staying the course?
• Mental health: If a situation takes a negative toll on your mental well-being and the future doesn’t look bright, closing the door is best.
• Compromised confidence: If you’re feeling less and less sure about the situation, this is an indicator that you may need to close the door.

This might show up with someone who keeps getting the same feedback at work, keeps trying to “fix themselves,” and slowly loses confidence. Or someone in a relationship where every attempt at repair becomes another argument about why they shouldn’t feel what they feel.

Not dramatic. Just repetitive.

How to overcome the sunk cost fallacy (and choose based on future alignment)

Overcoming this bias does not require becoming fearless. It requires changing the frame of the decision.

1) Separate past investment from present fit

A clean question that cuts through sunk cost thinking is:

If I had not invested anything yet, would I choose this today?

When people answer honestly, they often go quiet. Not because they suddenly know what to do. More because the spell breaks a little.

2) Decide using future cost, not past cost

Ask:

• What will this cost me in 6 months if nothing changes?
• What will this cost me in a year, emotionally, mentally, physically?
• What will this cost me in self-respect?

This is the flip. Past investment is fixed. Future consequence is still negotiable.

3) Take one aligned step, not a perfect plan

Many people stay because they believe leaving must be immediate and total. Often, it’s sequential:

• having the honest conversation
• setting a boundary you’ve been avoiding
• updating the resume or portfolio
• trying therapy/coaching
• reducing the commitment before ending it
• exploring a new path quietly and consistently

In practice, clarity often follows action.

I’ve tested this in small ways with clients who freeze when they think they need a final decision. We don’t decide the whole future. We choose the next step that reduces misalignment. The nervous system learns from movement.

4) Reframe “waste” as learning

This is where shame loosens, and something more realistic can move in.

Sometimes what we think is the wrong train was actually a necessary one:
It taught us what we don’t want.
It gave us tools for the next chapter.
It showed us how far we’ve come.
Even the detour had a purpose.

So, I don’t shame people for staying too long. I’m more interested in what it costs. And what it keeps costing.

Two research-backed pattern interrupters (to reduce sunk cost bias)

Verywell Mind’s 2025 update mentioned two strategies that line up with research I trust more than slogans.

• Considering how staying the course might affect others, Hamzagic and colleagues published work in Memory & Cognition in 2021 (first online in 2020) showing that the sunk-cost effect can shrink when continuing would harm other people. The “don’t waste” rule starts competing with an ethic of care.
• Assess your thoughts and feelings: Strough and colleagues in Psychology and Aging in 2016 tested interventions. People told to focus on what they thought and felt were more likely to give up failing plans than those told to focus on how to improve the situation.

That second one is awkward, because “improve it” sounds like the responsible option. And sometimes it is. But I’ve watched “improve it” become a trap, a way to keep investing indefinitely, because improvement gives you something to do instead of something to decide.

I’ve also been thinking about how “others” changes the effect in messier, everyday ways. Chen, Güney, and John published a paper in Acta Psychologica in November 2024 about decisions and predictions involving others, and it made me second-guess how stable the bias is across roles. It’s not always “stronger for self.” Sometimes it shifts with the role you’re in and what you think you’re responsible for.

Most importantly, ask yourself: Would I continue on this course if I hadn’t already invested the resources? If the answer is no, it’s a sign you should adjust your plans.

Set clear goals. Focus on the future instead of dwelling on past choices.

Quick Q&A

Closing thought

People often wait until things fall apart before they change direction. Some wait for a clearer sign. Some wait until they’re certain they won’t regret it. I get why. I also think the sunk cost fallacy feeds that waiting, because it keeps pulling attention back to what you’ve already spent.

You might not need a dramatic ending. You might not need anyone else to validate what your body already knows about the situation.

Which area of your life feels off-track right now: career, relationship, purpose? Share in the comments or pass this along to someone who may need the courage to change direction.

If you’d rather get these reflections as a weekly email than stumble on them randomly, there’s a free list for that.

Journal prompt:
What part of your life feels misaligned, and what might it look like to step off the train

References 

1. Gould, Wendy Rose. “Don’t Fall for the Sunk Cost Fallacy: Tips for Smarter Life Decisions.” Verywell Mind. Updated December 23, 2025. Reviewed by David Susman, PhD.
2. Arkes, Hal R., and Blumer, Catherine. “The Psychology of Sunk Cost.” Organizational Behavior and Human Decision Processes, 1985.
3. Kahneman, Daniel, and Tversky, Amos. “Prospect Theory: An Analysis of Decision under Risk.” Econometrica, 1979.
4. Samuelson, William, and Zeckhauser, Richard. “Status Quo Bias in Decision Making.” Journal of Risk and Uncertainty, 1988.
5. Dumsch, Amanda. “Sunk cost fallacy, how it affects career decision-making.” NIH Office of Intramural Training and Education (OITE) Careers Blog. November 22, 2021.
6. Tait, Veronika, and Miller Jr., Harold L. “Loss aversion as a potential factor in the sunk-cost fallacy.” International Journal of Psychological Research (Medellín), 2019; 12(2):8–16. doi:10.21500/20112084.3951
7. Haita-Falah, Corina. “Sunk-cost fallacy and cognitive ability in individual decision-making.” Journal of Economic Psychology, 2017; 58:44–59. doi:10.1016/j.joep.2016.12.001
8. Hamzagic, Zachariah I., Derksen, Daniel G., Matsuba, M. Kyle, Aßfalg, André, and Bernstein, Daniel M. “Harm to others reduces the sunk-cost effect.” Memory & Cognition, 2021; 49(3):544–556. doi:10.3758/s13421-020-01112-7
9. Strough, JoNell, Bruine de Bruin, Wändi, Parker, Andrew M., et al. “What were they thinking? Reducing sunk-cost bias in a life-span sample.” Psychology and Aging, 2016; 31(7):724–736. doi:10.1037/pag0000130
10. Chen, Zhiqin, Güney, Şule, and John, Richard S. “Sunk cost effects for thee but not for me: Decisions and predictions involving others.” Acta Psychologica, 2024 Nov; 251:104557. doi:10.1016/j.actpsy.2024.104557
11. Hamzagic, Zachariah I., and Krettenauer, Tobias. “Honesty and fairness reduce the sunk-cost effect.” Journal of Dynamic Decision Making, 2025. Published June 12, 2025. doi:10.11588/jddm.2025.1.106637