persuasion
Loss aversion
What is loss aversion?
Loss aversion is the way losing something hurts more than gaining the same thing pleases - roughly twice as much. The maths is identical; the feeling is not, which is why "don't lose this" pulls harder than "get this".
Also known as: losses loom larger, loss bias
The demo
The same £5, the same thing to do. Switch the framing from gain to loss and notice how much more the second version makes you want to act right now.
Flip between the two framings and watch the same £5 change weight.
What this demo shows (text version)
A single offer worth £5 for completing your profile, shown two ways. The gain frame reads "Earn £5 when you complete your profile", with a button to complete it. The loss frame reads "Your £5 bonus expires tonight - complete your profile to keep it", with a button to keep the bonus.
The reward is identical and so is the action; only the framing differs. The loss frame tends to feel more urgent because losing £5 stings about twice as much as gaining £5 pleases. That asymmetry is loss aversion - and the demo shows it is created entirely by wording, not by any change in the deal.
It was the same £5 and the same action both times. Framed as a gain it was easy to shrug off; framed as a loss about to expire, it suddenly felt worth doing now. Nothing changed but the wording around the word "lose" - and that did the work.
Loss aversion is honest when the loss is real - a genuine deadline, a discount that truly ends - and manipulative when the loss is invented to manufacture urgency. The same lever sits behind a friendly "your basket's about to expire" and a nasty "you'll lose everything if you leave". Watch which one you reach for.
It also shapes how people treat what they already have: defaults stick because switching feels like giving something up, and free trials convert because cancelling now reads as a loss. Design with that in mind, not against it - make the genuinely better choice the one that doesn't feel like a sacrifice.