Win at Life
The Sunk Cost Fallacy
Mindset Mechanics: Growth
Definition
The tendency to continue with something simply because you’ve already invested time, money, or effort into it – even if it’s no longer serving you.
What it is
You’re halfway through a film. It’s dragging. The acting’s wooden, the plot’s thin, but you sit through to the end. You’ve paid for it, after all.
You order something new at a restaurant. It’s awful. But you keep eating, because it cost £17.50 and you’re not leaving any of it behind.
You’ve been in a relationship for years. You’ve really tried and you’ve known it’s not working – but you stay … because of everything you’ve already put in.
This is the Sunk Cost Fallacy.
It’s one of those sneaky psychological tricks that keeps us stuck with things we no longer want, simply because we’ve already put effort, time, or money into them.
The cost is gone. Spent.
But our brains act like soldiering on will somehow make things better.
It won’t.
In behavioural economics, this is one of the most studied mental traps. What makes it so dangerous is that it often looks like loyalty, commitment, not wanting to be seen as flaky or a lightweight, or logic. It isn’t.
And it’s not just us, businesses do this – whole industries are built on this stuff.. Even governments fall for it. As I write this in 2025, *HS2 is still crawling forward. Labour started it, the Conservatives pressed on, and now it’s too expensive to abandon, even though many say scrapping it would make more sense than finishing what’s left.
The moment you spot it, though, things change. You get to step out of the loop. You’re allowed to stop, without guilt or drama or needing to explain it to anyone.
Why it’s useful
This isn’t just about finishing dodgy films or grim dinners. The Sunk Cost Fallacy drains your energy, attention, and time – and gives very little back.
It keeps us in jobs we’ve outgrown.
It makes us say yes when we mean no.
It keeps us going through the motions of things that used to matter but don’t anymore.
We tell ourselves it’s noble. That we’re seeing things through. But often, we’re just scared it’ll mean the earlier effort was a waste.
But here’s the thing: staying just because you’ve already stayed isn’t loyalty. It’s inertia.
There’s another way – one that’s calmer, simpler, and far more grown-up.
Real-life examples
You’ve been in your job for 14 years. It’s draining. But you stay, because it would feel like throwing all that time away.
You signed up for a course that hasn’t helped your career. It’s not what you need. But you push on, because you’ve already paid.
You’ve grown an Instagram following for a side hustle you’ve fallen out of love with. You keep posting, because you’ve built it up now.
There’s a friend who drains you. Always has something going on, never really listens, but you’ve known each other since college. So you keep meeting for coffee and calling it friendship.
All of these are decisions powered by the past. But the cost has already happened. The future is still wide open.
Try this today
Take a gentle scan of your life. Not urgently – just a light mental stroll with one eyebrow gently raised.
Where are you still saying yes out of guilt, stubbornness, or habit?
Ask yourself:
“If I had to choose this again today, knowing what I know now, would I?”
If the answer’s no… you’ve probably found your sunk cost.
Questions to Ask.
- What feels difficult to walk away from — and why?
- What would change if you weren’t trying to make the past count for more than it does?
- Who taught you that quitting was bad? And do you still agree?
Sometimes the strong move isn’t pushing through.
It’s stepping away with your head high and your shoulders down.
Optional challenge
Pick one small thing.
A newsletter you’ve never read.
A WhatsApp group that makes you sigh.
A book you feel you should finish, even though you hate it.
Say to yourself:
“The time I’ve spent is gone either way. But I get to choose what I do next.”
Then unsubscribe. Mute. Cancel. Archive. Let it go.
That little rush of relief you feel? That’s your sign. That’s the shift.
You don’t have to carry things just because you once picked them up.
A Buddh-ish Take
“When I let go of what I am, I become what I might be.”
– Lao Tzu
Not everything has to come with you.
Letting go isn’t weakness. It’s just you, making a better decision now that you know more.
Honouring the effort you’ve made doesn’t mean you have to keep going.
It meant something then. It doesn’t have to mean something forever.
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*HS2: A high-speed rail project intended to link London with the Midlands and the North. Widely criticised for huge cost overruns and route cancellations, it’s become a case study in how grand infrastructure plans can unravel – one eye-wateringly expensive mile at a time.