Why do New Year’s resolutions start with enthusiasm, only to quietly disappear by the end of February? It’s rarely a lack of motivation or willpower. Instead, it’s something far more human. In this Shifting Fast and Slow piece, we explore the planning fallacy, a behavioural bias that explains why our best intentions so often collide with real life. More importantly, we look at how behavioural science can help us get back on track without having to start over. From Intentions to Action: Why Plans Fall Apart Most of us genuinely believe that our future selves will have more time, energy and discipline than we do today. We picture a calmer version of ourselves who cooks every meal, exercises regularly and never forgets a health check or appointment. This is the planning fallacy in action. We tend to underestimate obstacles and overestimate our future capacity. As a result, we create plans that look sensible on paper but collapse when everyday pressures show up. Work deadlines, illness, stress and simple fatigue quickly expose the gap between intention and reality. What Is the Planning Fallacy? Behavioural science shows that people consistently underestimate how long tasks will take and how difficult they will feel. When planning, we assume things will run smoothly and ignore the very real disruptions that shape daily life. This is why resolutions often fail not because the goals are wrong, but because the plans are unrealistic. We plan for best‑case scenarios, then blame ourselves when reality doesn’t cooperate. Over time, this self‑blame makes it harder to re‑engage. Understanding the planning fallacy allows us to shift the focus from “why can’t I stick to this?” to “how can I plan more honestly?” Why Resolutions Drop Off Over Time As the weeks pass, even well‑intentioned plans can start to unravel. This usually happens for a few common reasons: -Goals are vague rather than behaviour‑specific -Progress relies on motivation, which naturally fluctuates -No plan exists for setbacks or disruption -One missed day is interpreted as failure, not friction When progress slows, the internal story often changes. “This is hard” quietly becomes “this isn’t for me”, and the behaviour is abandoned altogether. Shifting Fast and Slow: A Behavioural Science Approach The Shifting Fast and Slow approach offers a more realistic way forward. Instead of relying on motivation or perfection, it focuses on designing behaviours that work within real life. Shrink the Behaviour to Fit Reality Smaller actions reduce the mental barrier to starting. Rather than committing to “exercise five times a week”, begin with a ten‑minute walk after lunch. For medication routines, place tablets next to something already used daily, such as a kettle or toothbrush, to make the behaviour almost effortless. Create If-Then Plans for Friction Setbacks are inevitable, so plan for them. Simple if–then rules reduce decision‑making and stress. For example: If you can’t complete a full physiotherapy routine, then do two core exercises. If you miss a medication dose, then follow a safe catch‑up plan agreed with a clinician. Anchor New Habits to Existing Routines New behaviours are easier to maintain when they are attached to familiar routines. Brushing teeth, making dinner or boiling the kettle can all act as reliable cues. Taking medication after brushing your teeth or checking blood pressure before dinner removes the need to remember from scratch. Treat Missed Days as Data, Not Failure Behaviour change works best when it adapts to reality rather than fighting it. If you stop using a CPAP machine, skip blood glucose checks or fall behind on treatment exercises, treat that as information. Was it discomfort, side effects, time pressure or equipment issues? This mindset shift makes it easier to adjust the plan instead of abandoning it. Moving Forward Without Starting Again The planning fallacy doesn’t mean people lack discipline. It means we are human. By recognising how we misjudge time, effort and energy, we can design plans that are flexible, forgiving and far more sustainable. Shifting Fast and Slow reminds us that progress doesn’t require perfection. It requires plans that reflect how life actually works. Sometimes, staying on track starts with planning a little less optimistically, and a lot more honesty. Struggling with patient treatment adherence? The planning fallacy may be the missing insight. Reach out to Shift@hrwhealthcare.com or fill in the Contact Us form below to find out more. Apply Now!