I don't know if you recognise this, but I am a terrible leftover eater. I love to cook, and sometimes some really delicious food is left over. So I got myself those nice glass containers to save it, ready in the fridge for the next day's lunch or dinner. Well, truth be told: I have managed to fill my fridge with stacks of leftovers that never get eaten and end up shoved into the bin. A terrible waste, I know, but I think I have a leftover-use deficit. As a Behavioural Designer, though, that is far too easy an excuse, so it made me think about an interesting design question:
How do you design a country that stops throwing its food away? And where else could the same thinking quietly change a habit we all say we want to fix?
In searching for the answer I found an interesting case in South Korea. The conventional approach to food waste is the one we all know: awareness campaigns, posters about the hungry, gentle reminders to finish your plate. They change what people say and almost nothing about what people do. South Korea did something structural instead. It made households pay for the food they throw away, by weight, through special bags or metered bins, so that wasting food became a visible, recurring cost rather than a free and invisible act. The result is one of the most striking turnarounds anywhere: the share of food waste being recycled rose from a few per cent in the late 1990s to around ninety-five per cent today, with the volume of waste itself falling.
The behavioural science here is about how a price reshapes a decision without anyone being persuaded of anything.
When the cost of a behaviour is hidden, we barely register it; when it is made visible and personal at the moment of the choice, the decision changes on its own.
South Koreans did not become more virtuous about food. The bin started charging them, and the daily calculation quietly shifted. This is Behavioural Design working through the structure of a choice rather than through willpower or guilt. You do not convince people to waste less. You change what the wasteful option costs at the moment they choose, and the behaviour follows the new arithmetic.
So how do you put this to work, well beyond food? Here are three practical moves:
Make the hidden cost visible at the moment of the decision. People ignore costs they cannot see. Whether it is wasted budget, unused licences or abandoned meetings, surface the cost right where the choice is made, and watch behaviour adjust without a single lecture.
Attach a small, real cost to the behaviour you want less of. It need not be money. A required sign-off, a visible tally, a moment of friction at the point of waste makes the easy, careless option slightly less easy, which is often enough to change it.
Change the structure, not the awareness. Before you run another campaign, ask whether the wasteful behaviour is simply free and invisible right now. If it is, no amount of awareness will compete with that. Redesign what the choice costs instead.
For me, I quit jumping on the batch-cooking train. Batch cooking sounds like a great idea, but the hidden cost of buying all those vegetables in advance was that I always had too much fresh food at home, so the leftovers simply went unused.
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The Hawthorne effect: why being seen changes what we do
Now that we are on the subject of visibility. You have probably noticed that you tidy your desk, choose the healthier lunch or write the cleaner code a little more often when you know someone is watching. There is a name for this idea: the Hawthorne effect, the observation that people tend to change their behaviour when they know they are being watched. It takes its name from studies at the Western Electric Hawthorne plant in the 1920s, where researchers noticed that output seemed to rise simply because workers knew they were being studied. The original research has been much debated since, but the broader pattern, that being observed nudges our behaviour, is one most of us recognise in ourselves.The likely reason is that:
Being observed quietly raises the stakes of our own behaviour; we tend to hold ourselves to the standard we imagine the watcher expects.
The useful, and honest, application is that gentle visibility can support the behaviour you want, without any pressure or punishment. A shared progress board, a habit you track in the open, a goal you tell a colleague about: each adds a light layer of being seen, and the behaviour often follows. You do not need surveillance, only a little visibility. We tend to rise to what we know is noticed, so bring the behaviour you want quietly into view.
Here's to the stubborn optimists, who unlock the power of Behavioural Design for optimising work, life, and everything in between.
See you next week!
Astrid Groenewegen
Co-Founder of SUE | Behavioural Design Academy, Author of 'The Art of Designing Behaviour' / 'De Kunst van Gedrag Ontwerpen' and ‘De Gelukscode’.
Source:
South Korean Ministry of Environment; Volume-Based Waste Fee system (from 1995) and weight-based food waste fee (nationwide from 2013). Food waste recycling rose from about 2 per cent in the late 1990s to around 95 per cent.
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