The Reason You Can't Let Go (And What It's Quietly Costing You)
Here's an experiment that should make you slightly uncomfortable.
A psychologist at Cornell gave half his students a coffee mug. Standard university mug. Nothing special. He then asked the students who had the mug how much they'd want to sell it for. He asked the students who didn't have a mug how much they'd be willing to pay for one.
Same mug. Same room. Same day.
The sellers wanted an average of $7.12. The buyers offered $3.12.
Nobody had manufactured any attachment to this mug. Some students had owned it for about fifteen minutes. But the act of possession had already altered their sense of its value. Giving it up had become a loss. And as we established last time, losses loom roughly twice as large as equivalent gains.
This is the endowment effect.
And once you understand it, a huge amount of baffling human behaviour starts to make sense.
Why do people hold onto clothes they haven't worn in two years? Because throwing them away is a loss.
Why do investors keep holding shares long after any rational case for doing so has disappeared?
Because selling crystallises the loss, makes it real, and an unrealised loss still has a ghost of hope attached to it.
But here's where it gets genuinely strange.
The endowment effect doesn't only apply to physical objects.
It applies to ideas.
Once you've held a belief long enough, once you've built even a small part of your identity around it, abandoning that belief becomes a loss.
The person who has been politically convinced of something for twenty years isn't neutrally evaluating new evidence, they're protecting something they own.
The entrepreneur who has been building the same type of business for a decade isn't fully open to a completely different model. Not because they lack intelligence. Because what they have has become theirs. And losing what's yours hurts.
This is why genuinely changing your mind is one of the hardest things a human being can do. It isn't stubbornness in the crude sense. It's loss aversion applied to your own worldview.
There's a version of this that operates in business that most people completely miss.
Researchers presented two identical scenarios to a group of people:
A car dealer raises the price of a model by £200 above the standard list price due to a shortage. 71% of people view this as unfair.
A different dealer who had been selling at £200 below list returns to the standard price. 58% find this acceptable.
The financial outcome is identical. The car costs the same in both situations.
But the emotional reaction is completely different, because in the first scenario, the £200 feels like money being taken from the buyer's pocket. In the second, it feels like the removal of a gift.
The mug. The belief. The surcharge. The same mechanism runs through all of it: we feel the removal of something we have far more acutely than we feel the absence of something we never had.
The practical implication of all this cuts both ways.
If you're influencing someone else — in sales, in leadership, in any relationship — the most powerful question you can help them answer is not "what could you gain?" It's "what are you already losing?" Not in a manipulative way. In an honest one. If your product, your advice, or your recommendation genuinely solves a real problem, then the cost of inaction is real. Naming it is a service, not a trick.
This is also why free trials convert better than discounts. Once someone has experienced ownership — even briefly — the prospect of losing access to something feels more urgent than the appeal of gaining it in the first place. The trial creates an endowment. The discount doesn't.
But the more uncomfortable application is the one that faces inward.
The things you're not changing in your own life, the habit you haven't broken, the conversation you keep avoiding, the version of yourself you keep defending, ask yourself honestly: is that resistance based on genuine reasoning?
Or is it the endowment effect? Have you simply owned that pattern long enough that giving it up feels like a loss, even when keeping it is costing you something real?
Loss aversion doesn't care whether what you're protecting is worth protecting. It just makes giving things up feel harder than it is.
The first step is noticing when that mechanism is running the show.
The full psychology behind this, including how to apply it in your own decision-making and communication, is in the free Persuasion Psychology guide. Link in bio.
Till next time,
Jonny