Psychology says people who always imagine the best-case and worst-case scenario may be using a surprising anxiety strategy

Some people can rarely make an important decision without mentally running through several possible futures. Before a job interview, they imagine getting the position and being rejected. Before a trip, they picture an amazing vacation and everything going wrong. Before sending an important message, they consider the best possible response and the most disastrous one.

This habit may look like overthinking, but psychology offers a more complicated explanation. People who repeatedly evaluate both the best-case and worst-case scenarios may be engaging in prospection, mental simulation, defensive pessimism and uncertainty management. Sometimes these processes can improve preparation. At other times, they can turn into repetitive worry.

Psychology Says Some People Naturally Think in Multiple Futures

Psychologists Daniel Gilbert and Timothy Wilson have studied prospection, the human ability to represent and mentally experience possible futures.


Rather than simply waiting for something to happen, people can construct simulations of what might happen and predict how they will feel about it. This allows the brain to use imagined futures when making present decisions.


Someone considering a new job, for example, might imagine earning more money and enjoying the work. At the same time, they may picture losing work-life balance or discovering that the position is unsuitable.

That mental comparison can help transform an uncertain future into something psychologically more manageable.

Best-Case Thinking Can Create Motivation

Imagining the best possible outcome is not necessarily unrealistic optimism.

Research on mental simulation by psychologists Shelley Taylor and Liena Pham distinguished between imagining an outcome and imagining the process required to achieve it. Their experiments found that mental simulation can influence goal-directed effort and performance, with process simulation particularly useful for planning.

Consider a student preparing for an examination. Imagining the best-case outcome, receiving an excellent grade, can establish a desired destination. But imagining the process of studying, revising and completing practice papers can make the goal more actionable.

This is one reason future-oriented thinking can sometimes be productive rather than merely wishful.

Psychology Says Worst-Case Thinking Can Be a Coping Strategy

The more surprising explanation comes from psychologist Julie Norem's theory of defensive pessimism.

Defensive pessimism describes a strategy in which people deliberately set relatively low expectations and mentally simulate possible negative outcomes before a serious situation. Rather than simply assuming everything will work out, they think through what could go wrong and prepare accordingly.

For example, someone giving a presentation might imagine forgetting a key point, experiencing a technical failure or receiving a difficult question.

They may then prepare backup slides, save the presentation on another device and rehearse difficult questions.

In this situation, thinking about the worst case is not necessarily pessimism in the everyday sense. It can be a form of self-regulation. Norem's research specifically describes defensive pessimism as a strategy that can harness anxiety as motivation.

The Best-Case Plus Worst-Case Combination Can Be Powerful

Psychologist Gabriele Oettingen's research on mental contrasting provides another useful explanation.

Mental contrasting involves imagining a desired future and then comparing it with the obstacles standing between the person and that future. Research suggests this can strengthen goal pursuit when people have sufficiently strong expectations that the goal is achievable.

Imagine someone planning to start exercising. The best-case scenario might be feeling fitter and more energetic. The obstacle might be a busy work schedule. Instead of simply fantasizing about the result, the person identifies the obstacle and develops a practical response. That is very different from endlessly imagining disasters.

Psychology Says Uncertainty May Be the Real Trigger

For some people, however, constantly evaluating possible outcomes may reflect intolerance of uncertainty.

This psychological concept refers to difficulty tolerating situations where the outcome cannot be known in advance. A major 2026 preregistered meta-analysis involving 28,693 participants found robust associations between intolerance of uncertainty, worry and anxiety. The researchers described worry as an important cognitive process linking uncertainty with anxiety. This can create a cycle.

A person thinks, “What if everything goes perfectly?” Then, “But what if everything goes wrong?” Then another possibility appears: “What if something happens that I haven't considered?”

At that point, scenario planning can stop being preparation and become rumination or excessive worry. The difference is whether thinking produces useful action or simply generates more uncertainty.

Mental Simulation Can Help People Prepare for Problems

Research examining mental simulation more broadly has found that imagining future scenarios can influence behavior. A systematic review and multilevel meta-analysis covering 123 effects and 5,685 participants found a reliable positive effect of mental simulation on behavior change, although its effectiveness depended on the type of simulation being used.

This helps explain why people who constantly think through possible outcomes can sometimes appear unusually prepared.


A traveler who imagines missing a flight might leave earlier. A professional who imagines a presentation failing might carry a backup copy. A parent anticipating a child's possible reaction might prepare several ways to explain something. The imagined negative scenario has produced a real-world precaution.

When Scenario Planning Becomes Overthinking

The problem begins when the brain treats every possible outcome as something that must be solved before action can happen.

Someone might repeatedly rehearse every possible response to a conversation but still feel unprepared. Another person might research every possible outcome of a decision without ever making the decision.

That distinction is important because adaptive planning reduces uncertainty through action, while excessive worry often creates more questions.

Research on intolerance of uncertainty supports this distinction: psychological treatments that specifically target intolerance of uncertainty have been associated with reductions in both uncertainty intolerance and worry.

The Psychology Behind Best- and Worst-Case Thinking

People who habitually evaluate both extremes may therefore have a strong tendency toward future-oriented cognition.

They may be planners who use mental simulation to prepare. They may use defensive pessimism to manage performance anxiety. They may practice mental contrasting by comparing goals with obstacles. Or, if the process becomes repetitive and uncontrollable, uncertainty intolerance and worry may be involved.

So the person who says, “I always think about what could go right and what could go wrong” is not necessarily pessimistic or anxious. Sometimes they are simply trying to make an unpredictable future feel a little more predictable.

The important psychological question is not how many scenarios someone imagines. It is whether those scenarios help them act, or keep them stuck thinking.

FAQs

Is imagining the worst-case scenario a sign of anxiety?

Not automatically. Defensive pessimism can involve imagining negative outcomes as a way of preparing and reducing anxiety. It becomes more concerning when worst-case thinking becomes persistent, uncontrollable or interferes with decisions and daily life.

Why do some people always think about the best and worst possible outcome?

This can reflect prospection, mental simulation, planning, defensive pessimism or a desire to manage uncertainty. Different people can engage in the same behavior for very different psychological reasons.