The intriguing aspect of planning error is that people simultaneously harbor optimistic expectations about a specific future task and more realistic ideas about how long it took them to do something in the past. When it comes to plans and predictions, people may know the past well, but they are doomed to repeat it. The hallmark of planning error is that people admit that their past projections were overly optimistic, but insist that their current projections are realistic. Scheduling error requires that the current forecasts of task completion times are more optimistic than assumptions about past completion times for similar projects, and that current forecasts of task completion times are more optimistic than the actual time for completion of activities. [Sources: 2, 10, 15]
Scheduling bias results from the tendency to overlook distribution data and adopt what might be called an internal forecasting approach that focuses on the building blocks of a particular problem rather than the distribution of outcomes in similar cases. An internal approach to evaluating plans can lead to underestimation. For example, academics and writers are known to tend to underestimate the time it takes to complete a project, even if they have significant past failure to meet planned schedules. This phenomenon sometimes occurs regardless of whether people realize that past tasks of a similar nature took longer than usually planned. [Sources: 2, 5]
First proposed by Daniel Kahneman and Amos Tversky, scheduling error refers to a phenomenon in which the time it takes to complete a task is systematically underestimated. As we discussed earlier, a scheduling error causes students to underestimate the amount of time it will take to complete their homework, which can result in them wasting all night or missing deadlines. Planning error is a phenomenon in which forecasts of how long it will take to complete a future task exhibits an optimistic bias and underestimates the time it will take. This phenomenon occurs regardless of whether people realize that past tasks of a similar nature took longer than normally planned. [Sources: 5, 6, 10, 15]
Prejudice only involves the prediction of their own tasks; when outsiders predict when an activity will be completed, they are often pessimistic and overestimate the time it takes. In 2003, Lovallo and Kahneman proposed an expanded definition that tends to underestimate the time, cost, and risk of future actions, while overestimating the benefits of the same actions. In 2003, Daniel Kahneman and his new research partner Dan Lovallo re-examined the wrong idea of the plan and found that people not only underestimated the time required to complete certain tasks, but also underestimated the negative consequences and costs. A specific task. [Sources: 6, 8]
Kahneman and Tversky initially explained the error by imagining that planners focus on the most optimistic scenario for completing a task, rather than using their full experience of how long similar tasks take to complete. The original explanation for the error by Kahneman and Tversky was that planners focus on the most optimistic scenario for completing a task, rather than using their entire experience in terms of how long similar tasks take to complete. One explanation, focusism, suggests that people fall prey to a planning error because they only focus on the task ahead and do not consider similar tasks from the past that took longer than expected. [Sources: 5, 8]
Examples of planning errors in action can be as large as a massive public works program like Big Dig in Boston (the highway project ended nine years late and $ 22 billion over budget), or as small as seemingly fast commission that somehow takes a day. Whatever the outcome, the planning fallacy stems from two fundamental mistakes, as Kahneman wrote in his memoir Thinking Fast and Slow. Scheduling mistakes are hard to avoid, from miscalculating travel times to your destination – if you think you can beat your app’s rating – to thinking you can leave your presentation at the last minute. [Sources: 3, 4]
Planning bias was first proposed by Daniel Kahneman and Amos Tversky in 1979. It is a cognitive bias that is caused by our inherent belief that we cannot predict negative events, which leads to concerns about the time, cost, or risk associated with performing tasks. The forecast is inaccurate. Regardless of past experience with similar tasks. Nobel laureate Daniel Kahneman and his partner Amos Tversky first made the main point in an influential article published in 1979, namely Humans cannot estimate how long it will take to complete the task. As described in Kahneman’s recent book “Thinking Fast and Slowly”, a study found that the typical homeowner expects the cost of his home renovation project to be about $19,000. [Sources: 1, 14]
In such studies, people predict how long it will take to complete an upcoming project and also report how long it took them to complete very similar projects in the past. For example, people imagine and plan specific steps they will take to complete a targeted project. The people who make the plan can eliminate factors that they think are irrelevant to the specifics of the project. [Sources: 8, 9]
At the same time, leaders may favor forecasts that are more optimistic than others, which gives people an incentive to plan inaccurately based on intuition. Cognitive biases such as optimism bias (the tendency for people to expect positive results from their actions) and overconfidence have been suggested as causes of planning error. Oxford University researcher Bent Flivbjerg has received growing evidence that optimism bias is one of the most important biases when it comes to predictive factors in project planning. [Sources: 7, 13]
Kahneman and Tversky, and then Dan Lovallo, suggested that the appearance of the forecast helps to reduce planning error. For example, by encouraging people to form “implementation intentions” during forecasting — by getting them to complete parts of a task at specific times and on specific dates — people are more likely to perform those activities and, therefore, are less prone to planning errors. [Sources: 9, 13]
Predicting how long a task will take is unrealistic behavior. It is a deeply ingrained behavior and requires some practice to find out that you are doing it. After obtaining an objective estimate of the time required to complete the project, you need to ensure that you have the time and resources to complete your plan. [Sources: 4]
Make them urgent by setting deadlines as close to the current moment as possible. Determine if you are the priority organizer, planner, arranger, or spectator so you can plan accordingly. [Sources: 11]
— Slimane Zouggari
##### Sources #####
[0]: https://harappa.education/harappa-diaries/planning-fallacy-its-meaning-and-examples/
[1]: https://hbr.org/2012/08/the-planning-fallacy-and-the-i
[2]: https://www.bbntimes.com/global-economy/the-planning-fallacy-or-how-to-ever-get-anything-done
[3]: https://qz.com/work/1533324/daniel-kahnemans-planning-fallacy-explains-why-were-bad-at-time-management/
[4]: https://nesslabs.com/planning-fallacy
[5]: https://en.wikipedia.org/wiki/Planning_fallacy
[6]: https://academy4sc.org/video/planning-fallacy-bit-off-more-than-you-can-chew/
[7]: https://thedecisionlab.com/biases/planning-fallacy/
[8]: https://psynso.com/planning-fallacy/
[9]: https://spsp.org/news-center/blog/buehler-planning-fallacy
[10]: https://herdingcats.typepad.com/my_weblog/2015/05/the-fallacy-of-the-plannig-fallacy-1.html
[11]: https://www.entrepreneur.com/article/350045
[12]: https://blog.firmsone.com/overcoming-the-planning-fallacy/
[13]: https://www.washingtonpost.com/business/the-planning-fallacy-can-derail-a-projects-best-intentions/2015/03/05/fcd019a0-c1bc-11e4-9271-610273846239_story.html
[14]: https://www.mcguffincg.com/the-planning-fallacy/
[15]: https://medium.com/gravityblog/the-planning-fallacy-3af4bb20493c