When shortage becomes behaviour

How behavioural science is key to understanding a new world of supply shocks

A couple of weeks ago, on our family WhatsApp chat, my mother said she was filling up the car with petrol, ‘just in case’. The war in the Middle East was not looking good, and there was a chance it would hit petrol supplies before long. This is familiar behaviour for her, from years of living in the countryside, where if you did not have something, it was a twenty-mile round-trip to buy it. And memories of being snowed in for weeks and the oil crisis of the 70’s meant that ‘being prepared’ was a family mantra. I ignored this myself, but then the following week did exactly the same.

There was nothing to suggest any concern at the petrol station - deliveries were arriving, there was no official shortage, and it was no busier than usual. The price of petrol had gone but not by all that much.

But we know that fuel crises rarely begin with the empty pumps. Instead, they start with behaviours like those of my mother and myself - small changes in behaviour, each individually sensible, but when done by many people, it’s destabilising. Systems are not only disrupted by external shocks but are instead gradually reconfigured by people’s behaviour in response to these shocks. Behavioural science captures this through the concept of adaptive purchasing behaviour (APB), defined as changes in consumption in response to perceived or anticipated scarcity. This framing matters because it moves away from the misleading language of ‘panic’ and instead recognises these actions as reasonable attempts to manage uncertainty (Ntontis et al., 2022).

The critical issue, therefore, is not only whether there is enough fuel due to events in the Middle East, but how behaviour evolves once the possibility of shortage becomes socially real.

Anticipation, timing, and the reorganisation of demand

It is clear that we respond not only to objective conditions but to expectations we have about future availability: I am not buying petrol now as there is a shortage, but I am anticipating there to be one in the future. And these expectations are formed through a complex environment of signals rather than through formal information alone. We are exposed to price movements (have prices gone up, by how much?), media tone is there a sense of alarm, impending doom?), expert commentary (what is the analysis of shipping volumes), peer behaviour (the fact my mother filled up her car got me thinking), and everyday observation (does the petrol station seem busier?) combine to create the sense of a trajectory, if where the situation is probably heading. This means that behaviour often shifts not when people know there is a shortage, but when the possibility it becomes plausible enough to warrant precaution.

This anticipatory dynamic has been observed before, of course. During the early stages of the COVID, pandemic, purchasing behaviour peaked in advance of formal restrictions, indicating that we respond to perceived futures rather than confirmed realities. In fuel markets, this temporal shift is particularly consequential as consumption is flexible in timing: drivers can bring forward demand, refuelling earlier than necessary so they can reduce perceived future risk. What emerges is not an increase in total demand in the immediate sense, but a redistribution of demand over time. This places pressure on systems designed for steady throughput, creating bottlenecks that can resemble or precipitate genuine shortage.

The significance of this reorganisation is often underestimated. Policy and industry tend to focus on aggregate supply and demand, but behavioural shifts operate at the level of timing, not just volume. When millions of individuals act to secure access earlier than they otherwise would, the system experiences a surge that it is not configured to absorb. The result is that the perception of risk begins to materialise as operational strain.

Despite this being well understood by analysts and policymakers, a persistent public narrative is that shortages are driven by extreme behaviour, by a minority of people hoarding resources. The evidence contradicts this perspective - data from the pandemic show that demand spikes were mainly the result of modest adjustments distributed across large populations rather than dramatic over-purchasing by a few. We did not typically buy excessive quantities of single items; instead, we added a few extra items to baskets, shopped slightly more frequently, or brought forward purchases we would have made later.

This phenomenon, often described as ‘accidental stockpiling’, is critical to understanding fuel dynamics. In this context, drivers do not need to store large quantities of fuel to destabilise the system.

Social amplification and the construction of crisis

To understand how these behavioural shifts escalate, it is necessary to move beyond individual decision-making and consider the broader environment in which those decisions are made. The social amplification of risk framework suggests that risks are not merely communicated but are interpreted, intensified, and transmitted through social systems, including media, institutions, and interpersonal.

In the case of fuel shortages, amplification occurs through the interaction of multiple signals. Media coverage frames the situation, perhaps emphasising urgency or instability. Price increases provide a tangible sign that conditions are getting worse. Visible cues, such as queues and petrol stations that have run out, translate abstract risk into lived experience. These signals reinforce one another, producing a cumulative effect in which the perceived severity and immediacy of the situation increase.

In fact, research demonstrates that exposure to scarcity cues increases purchasing behaviour, and real-world data reinforce this dynamic. The UK fuel shortages of 2021, characterised by high visibility and widespread queues, produced a substantial increase in demand, whereas less visible disruptions in 2022 did not generate comparable behavioural responses. The underlying conditions may be similar, but the behavioural outcomes differ according to how those conditions are perceived and verified.

Crucially, amplification is not simply about the volume of information but about its interpretation. As signals accumulate, they shift how individuals understand the situation. We start to see risks as more personal, more immediate, and more critical, which means the threshold for behavioural change lowers, meaning that the situation can rapidly escalate.

Lived adaptation

While much of the literature on shortages focuses on demand spikes, emerging evidence suggests a broader pattern of behavioural adjustment. Many individuals are not increasing consumption but actively restructuring their everyday practices in response to rising prices and constrained supply.

Reports from multiple countries show people reducing discretionary travel, grouping journeys, switching transport modes, and cutting domestic energy use. Others are heating fewer rooms, substituting fuel sources, or abandoning heating altogether where costs become prohibitive. These behaviours reflect constraint rather than excess, shaped by affordability, infrastructure, and necessity.

This reveals a dual dynamic. Some individuals bring consumption forward, contributing to demand spikes, while others ration and reduce use, often at significant personal cost. Adaptive behaviour is therefore heterogeneous, shaped by resources and context. Those with greater flexibility can adjust more easily, while others face trade-offs between essential needs.

From price shock to supply constraint

A critical question is whether the current energy disruption represents a continuation of recent crises or a qualitatively different form of risk. Much of the behavioural evidence on shortages comes from contexts where overall supply remained largely intact, but distribution bottlenecks and demand synchronisation created the appearance of scarcity.

However, energy operates differently. It is not simply a consumer good but an input into production systems. Disruptions to oil and gas supply can propagate through the economy via increased transport costs, reduced fertiliser production, and constraints on energy-intensive agriculture.

There is evidence that fertiliser production is particularly sensitive to energy prices, and that agricultural systems are highly dependent on fuel inputs. During the COVID pandemic, global oil demand fell by approximately 18–20 million barrels per day, reflecting an unprecedented contraction in activity. By contrast, current disruptions are framed in terms of constrained supply rather than reduced demand, suggesting a different form of system stress.

The distinction is important because systems respond very differently to falling demand than they do to falling supply. When demand collapses, as in 2020, goods still exist in sufficient quantity. So, the system has slack; the problem is that consumption has dropped away.

Of course, when supply falls, slack disappears. But demand does not fall at the same rate as availability does, meaning the system is forced to adjust through higher prices, reduced access, and strained distribution.

So while initially shortages are driven by behaviour, by people bringing forward purchases or reacting to signals, it becomes one where the system itself imposes limits. Behaviour no longer just reveals scarcity; it begins to operate within it.

This has a range of implications: large urban centres depend on continuous inflows of goods sustained by complex logistics networks. Fuel disruption places pressure on these systems at multiple points, affecting transport, packaging, and distribution. As costs rise and uncertainty increases, suppliers may adjust their behaviour, prioritising local markets over more distant urban centres.

This introduces the possibility of geographical fragmentation, where goods remain available within the system but are no longer evenly distributed. Such dynamics have historical precedent, where shortages have emerged not from an absolute absence of supply but from failures of distribution.

From a behavioural perspective, these structural pressures interact with demand dynamics. Early signals of scarcity trigger adaptive purchasing, which further strains distribution systems already under pressure. The result is a non-linear escalation in which behavioural and structural dynamics reinforce one another.

Policy failure and the limits of communication

Policy responses to shortages have traditionally relied heavily on communication. Governments issue reassurances, provide updates, and encourage calm behaviour. While necessary, this approach rests on an assumption that behaviour can be stabilised through information alone.

Evidence suggests this assumption is limited. Under conditions of social amplification, communication becomes one signal among many. Where communication is perceived as weak or unclear, visible signals quickly dominate, fuelling behavioural escalation. Moreover, communication strategies can inadvertently amplify risk, particularly where they signal loss of control or fail to align with lived experience.

If shortages are co-produced by behaviour, then managing them requires more than communication. Government responses will need to combine communication with structural interventions that shape how demand and supply interact.

Evidence from Thailand illustrates how these dynamics play out in practice. Policymakers debated the role of price signals, recognising that suppressing prices may reduce incentives to conserve fuel, while gradual increases can distribute adjustment across the system. At the same time, businesses optimised logistics, governments diversified supply sources, and policies promoted alternative fuels.

More broadly, resilience approaches emphasise demand management, transparency, and preparedness measures that reduce the likelihood of sudden behavioural shifts. These interventions operate upstream, shaping the system within which behaviour occurs rather than attempting to correct behaviour after the fact.

This reflects a broader shift in behavioural public policy towards integrating behavioural insights with system design and structural intervention.

Collective responses and the politics of price

Much of the analysis of fuel crises assumes that public response will take relatively predictable forms: reduced consumption, substitution, or precautionary purchasing. Yet history suggests that behaviour under conditions of sustained pressure does not always remain within these boundaries. Under certain conditions, responses can become collective, organised, and explicitly political.

The Gilets Jaunes movement in France provides a contemporary example. Initially triggered in 2018 by planned increases in fuel taxes, the protests rapidly expanded into a broader expression of discontent over living costs, inequality, and perceived disconnection between policymakers and everyday life. What began as a response to fuel prices evolved into a sustained national mobilisation, with road blockades, demonstrations, and widespread disruption. Fuel, in this case, acted as a focal point for deeper tensions around fairness and economic burden.

Similarly, the UK fuel protests of 2000 demonstrated how quickly disruption can escalate when supply, price, and legitimacy intersect. Protests against rising fuel duties led to blockades of oil refineries and distribution depots, resulting in widespread shortages across the country within days. Crucially, the speed and scale of disruption were not solely the result of reduced supply, but of how quickly distribution networks and consumption patterns adjusted under pressure.

These examples echo earlier forms of collective action, such as the autoriduzione movement in 1970s Italy, where groups of workers and households resisted price increases by collectively refusing to pay higher rates for essential goods and services. Across these cases, a common pattern emerges: when essential goods become more expensive under conditions of perceived unfairness or constraint, behaviour can shift from adaptation to contestation.

From a behavioural perspective, such responses can be understood as an extension of the same dynamics discussed earlier. Social amplification not only increases perceptions of scarcity; it can also amplify perceptions of injustice. Rising prices, visible inequality in impact, and uncertainty about how costs are distributed across society can create conditions in which collective action becomes more likely.

Importantly, these responses are difficult to predict using conventional models. They do not follow directly from price signals or supply constraints, but emerge from the interaction of economic pressure, social coordination, and moral judgment. As such, they represent a form of non-linear behavioural escalation, in which the nature of response shifts qualitatively rather than simply intensifying.

The implication is that public behaviour in fuel crises cannot be assumed to remain within the bounds of individual adaptation. Under sustained strain, responses may become collective, coordinated, and contested. The system is not only subject to pressure from consumption patterns, but from challenges to its perceived legitimacy.

Conclusion

What this reveals is a limitation in how behavioural science has typically approached problems of this kind. Much of the field has been built around understanding individual decision-making, such as the way we all respond to information, incentives, and choice environments. But the dynamics that are rapidly moving in our direction do not sit neatly at that level. Instead, they emerge when behaviour interacts with systems that are themselves under strain.

In these contexts, behaviour is not simply something to be influenced after the fact. It is part of the system’s operating logic. Small shifts in timing, perception, and expectation can reorganise demand, alter distribution, and, under certain conditions, begin to reshape the material reality they are responding to. The boundary between perception and outcome becomes less clear. Behaviour does not just follow events; it brings them about.

But just as importantly, behaviour does not remain confined to adapting to shortages. Under sustained pressure, it can become collective, coordinated, and political. As pressures intensify, questions of access, fairness, and burden-sharing become more visible. Behaviour shifts from managing personal exposure to contesting the terms of the system itself. This has significant implications for behavioural science. Interventions that focus narrowly on correcting individual behaviour are unlikely to be sufficient where outcomes are driven by collective dynamics and contested legitimacy.

Perhaps a more useful approach is to treat behaviour as something that unfolds across networks: this means paying attention to timing, visibility and to coordination. It also means engaging more directly with the political dimensions of behaviour: how people interpret fairness, how they respond to perceived imbalance, and how collective responses emerge under shared conditions of strain.

For behavioural science, the task is therefore not only to better predict individual decisions, but to understand how behaviour scales, aligns, and becomes organised. This involves moving beyond models that assume stability and compliance, towards approaches that can account for feedback, non-linearity, and contestation.