The Psychology Behind Behaviour Change: Why Do New Year’s Resolutions Fail?

The Psychology Behind Behaviour Change Why Do New Year’s Resolutions Fail

Author: Claudia M. Elsig, MD

Making a New Year’s resolution is a ritual for many. But how often do we promise ourselves a new regime at New Year only to find we fall at the first hurdle? Remarkably, eighty per cent of people fail at New Year’s resolutions, ditching them by mid-February.1 A report by Time says just 8 per cent of people stick with their resolutions for the entire year.2

Whether resolutions are picked to achieve a personal accomplishment like losing weight, giving up alcohol, getting fit, or changing an undesired trait or behaviour, perhaps to sort out a troubled relationship, or reach a business goal, why aren’t we more successful at seeing change through?

This blog examines the psychology behind behaviour change to shed light on why so many New Year’s resolutions fail.

Why do we make New Year’s Resolutions?

The tradition of making New Year’s resolutions goes back to ancient times. Four thousand years ago, the Babylons made promises to get on the right side of their gods.3 A similar practice happened in ancient Rome.

Long ago, New Year celebrations were embedded into spirituality. For Christians, the first day of the year became one of reflection and resolving to do better in the future.

Now, New Year’s resolutions extend beyond religion. Many people make promises to themselves, usually for self-improvement or to kick an unhealthy habit. The New Year continues to symbolise an opportunity for a fresh start.

What is behaviour change?

Behaviour change involves changing habits for the long term. Targets for behaviour change are often things like eating more healthily, reducing alcohol consumption, quitting smoking, exercising regularly, practising safe sex, and improving well-being.

Changing behaviour involves modifying actions, attitudes, and habits. Making a significant behaviour change, like overcoming an addiction, requires a substantial amount of time and effort and proper professional support.

Why is it so difficult to change behaviour?

First, it is essential to understand that changing behaviour isn’t a straightforward linear process. Behaviour change is complex because a person must disrupt a current habit while simultaneously fostering new and unfamiliar actions. Something as simple as drinking an extra cup of water each day can take an average of two months to become a consistent, habitual behaviour.4

When behaviours are ingrained, they become habits that get performed automatically without thinking. This poses a significant challenge when attempting to change those behaviours because the subconscious mind is involved.

There are many elements involved in changing behaviour. It’s not purely about intention. A key aspect of behaviours is our environment, so attempting to change a behaviour without changing the environment can make it incredibly difficult. Like for example, trying to quit drinking alcohol but still meeting friends at the bar.

Psychological self-sabotage can also thwart change. There can be a preconceived sense of hopelessness. A person’s internal narrative may say, for example, “I’ll never be able to lose the weight” or “I can’t quit smoking”. Even when individuals know that behaviour change will benefit them, they can still have difficulty committing to it.

Maintaining motivation when changing behaviour can also trip people up. It takes a lot of self-control to stay on the right path. This is where peer support can help. Alcoholics Anonymous is one example of a support group that can help steer people away from temptation.

It’s not enough to decide to change behaviour and enact it. The new behaviour will need to be performed persistently over time to make any new replacement behaviour the norm. Unexpected triggers can derail the good work, so individuals must become more aware of what these triggers are and be able to resume progress if a relapse occurs.

For success, it’s critical not to set unrealistic goals or try to make a colossal change quickly.

Behavioural change theories

There are several theories in the field of psychology about behaviour change. These include:

  • The theory of planned behaviour/reasoned action
  • Social cognitive theory
  • The transtheoretical model
  • Information–motivation–behavioural skills model
  • Behaviour change wheel & COM-B model
  • CEOS theory

The theory of planned behaviour/reasoned action, developed by Martin Fishbein and Icek Ajzen in the 1970s, supports the idea that the more positive a person is about changing their behaviour, or the stronger their intention is, the more likely they are to affect long-term change successfully.5

Social cognitive theory (SCT), developed by Albert Bandura in 1986, posits that many behaviours are learned by observing others in a social environment (modelling). Rewards and punishments reinforce or reduce the likelihood of behaviours. Social surroundings inhibit actions or encourage them. Bandura also found that people’s beliefs about their abilities affected outcomes.6

The transtheoretical model was developed in the 1970s by James Prochaska and Carlo Diclemente. They suggested that “health behaviour change involves progress through six stages … pre-contemplation, contemplation, preparation, action, maintenance, and termination.”7

The model posits that people must want to change, not just act, and must prepare. Perhaps we can see why so many New Year’s resolutions fail using this theory. People often make New Year’s resolutions just a few weeks or even days before the 1st of January. There is no time for ‘pre-contemplation’, ‘contemplation’ or ‘preparation’. The idea of changing a behaviour needs time to develop. There also needs to be a plan to overcome obstacles or temptations.

The information–motivation–behavioural skills model was developed in 1992 by Jeffrey D. Fisher and William A. Fisher as they sought to understand the mechanism behind HIV-risk behaviour change. The model asserts that health-related information, motivation, and behavioural skills are fundamental determinants of health behaviours.8

The behaviour change wheel & COM-B model, developed in 2011 by Susan Michie, Maartje M van Stralen and Robert West, combines different behaviour change frameworks. The theory is based on the idea that behaviour occurs as an interaction between capability, opportunity, and motivation.9

CEOS Theory is another model that helps us understand why behaviour change is challenging. CEOS stands for Context, Executive, and Operational Systems Theory. It recognises hierarchical control systems within human function and provides a model for understanding why some behaviour changes are more difficult to maintain.

CEOS theory works on the concept that there are conscious and non-conscious influences on behaviour and that two competing processes or systems in human functioning generate behaviours.10

The theoretical complexities of behaviour change

The sheer number of theories on behaviour change illustrates the complexity of this field. So many factors affect an individual’s behaviour including households, wider society, and culture. 

Often, setbacks are part of behaviour change, but how they are managed according to theories can influence the long-term outcomes.

For example, research into smoking cessation discovered that individuals who stopped smoking cigarettes took several attempts to quit. Under the transtheoretical model, relapsing is part of the change process and is viewed as an opportunity to develop flexibility, self-compassion and curiosity.11

Mental illness and behaviour change

Mental illness affects how a person feels, thinks, and behaves. In many cases, people with mental illnesses experience challenging behaviour incidents and face barriers to behaviour change processes. Change is a complicated process and failed resolutions can worsen mental health, exacerbating feelings of failure and worthlessness.

Treatment of chronic diseases, like addiction, involves changing deeply rooted behaviours. Addiction is a severe mental disorder and frequently occurs with other mental illnesses, such as post-traumatic stress disorder and affective disorder.

Since mental health issues are commonly experienced – statistics by the World Health Organization reveal that in 2022, one in every eight people in the world live with a mental disorder. Mental health charity, MIND, reports that one in every four people experience a mental health problem of some kind each year in England. So, this too may be a contributing factor as to why so many New Year’s resolutions fail.

CALDA: your personalised way to freedom

Specialist treatment, such as the rehabilitation programs offered at CALDA, is necessary to correct physical health imbalances and address complex psychological dysfunction.

CALDA’s personalised programs are designed to create lasting behaviour change. We help set actionable goals and empower individuals to master techniques to recognise and change ingrained behaviours.

One of the most effective ways of effecting behaviour change is through a specific type of therapy, known as CBT – cognitive behavioural therapy. CBT helps to change associations with unhealthy behaviours and replace them.

At CALDA, individuals are supported by a range of holistic therapies for body and mind to facilitate psychological wellness and a mindset for change.

If you would like to know more about how our programs can support behaviour change, please get in touch. Our Medical Director, Dr Claudia M. Elsig, will thoroughly explain the process. We offer absolute discretion and privacy.


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