Why do we underestimate how long it will take us to complete things? In his research, Roger Buehler and his colleagues highlighted a ‘Planning Fallacy’.

The Planning Fallacy describes the fact that people tend to underestimate how long it will take them to complete tasks. We do this because we rely too much on what we intend to do. We tend to ignore our own past experiences and so ignore how long it has taken us to do similar things in the past.

However we don’t seem to do the same for others. When we think of how long it will take someone else to do something, we take into account their past experience and are less biased by their personal intentions.

This bias towards our own intentions can lead us to making bad plans and not giving ourselves enough time to complete tasks.

But, asking for someone else’s opinion can help you make a more accurate plan. They will be more accurate with timings and help you see clearly what you can realistically achieve.

Why does basing our plans on our intentions lead us to plan for things we might not be able to quite achieve?

This comes down to the ‘Dunning-Kruger’ effect. This is the idea that when we are bad at something, we believe we are better at it than we actually are.

We do this because we cannot recognize what being ‘bad’ or ‘good’ at the task actually looks like. The skills that we need to be good at the task are the same skills that we need to be able to understand why we are bad at it.

An example of this could be baking. If an amateur baker ends up making a bad cake, they might think that they followed their recipe really well, but that it was just a bad recipe. They do this because they lack the skills to tell them what part of the baking process they didn’t do properly.

We can make our plans better by getting our time frame right and being aware of our own abilities. But how do we make sure we then frame our plans in the right way?

Gabriele Oettingen has done a lot of research into the best type of plans. She found that ‘plans’ that are simply positive fantasies can actually be bad for trying to achieve goals. An example fantasy would be ‘I would love to get that job when I quit my job next week.’

She found that these fantasies aren’t enough, and that a key component for successful planning is thinking about the obstacles that might get in the way of achieving what you want. Identifying what stands between you and fulfilling your goal can make you more committed to carrying out your plan and allow you to deal with each obstacle when it pops up.

Oettingen coined the term ‘Mental Contrasting’ for this. You should contrast the fantasies you have with the realistic obstacles that stand in your way. Doing this brings you back down to earth and calls you to act so you can overcome specific hurdles. An example would be ‘I would love to get that job when I quit my job next week, but my CV is not up-to-date yet.’

Identifying the obstacles that can stand in our way goes a long way to helping us to stick to our plans. However, when these obstacles are complicated or tempting it can be hard to see a simple way to overcome them.

One way to make this easier could be to use Implementation Intentions, or ‘If-Then’ plans. These are plans where you state that ‘if’ something happens, ‘then’ you will do carry out a certain behavior. For example: If I see a tempting unhealthy snack, then I will eat an apple instead.

By specifying the actions you will carry out in certain situations, Implementation Intentions take away the effort of trying to stick to your plan. The ‘If’ part sets up what situations or triggers will help or hinder your goals, and then ‘then’ part specifically outlines what actions you will take to achieve the goal when they pop up. These If-Then plans make you implement what you intend to, and so can be particularly useful for complex plans.

We can underestimate our workload, overestimate our abilities and focus too much on what we want rather than what we need to overcome. All of these can contribute to why we might not stick to our plans.

To make your plans better, ask friends or colleagues for help planning, look at your past experiences, and identify the obstacles that get in the way of your final goal.