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Planning Fallacy: Being realistic about how much time you have

Planning Fallacy: Being realistic about how much time you have

Below are past conversations I've had with students. They are typical of discussions I have every time an assignment is due.

Student One: Professor Akil, I forgot to print my references and I can’t use the printers at the library because I don’t have my student ID. Do you want me to print them out later and bring them to you this afternoon?

Dr. Akil: No thank you. I will just have to grade what you turn in.

(I won’t even address the part where the student asked, “Do you want me to print them out later…”)

Student Two: Dr. Akil, I am glad I caught you! My presentation is prepared, however, I didn’t know that I had to speak today. I thought I was scheduled to go Wednesday.

Dr. Akil: Well that’s good. Then it worked out.

Student Two: Not exactly. Since I didn’t know I had to present today, I didn’t dress properly (the student had on a t-shirt, shorts and flip flops). So my question is, will you take off points for me not dressing according to code?

Dr. Akil: I understand that you confused the date, but I still have to apply the same standard for the dress code that I use when grading everyone else.

The student then looks at another student with an expression that I read as, “Can you believe this guy?”


With students it’s difficult to tell the difference between a ‘real’ excuse or something made up to gain leniency. Either way, it is almost always a mistake in planning, as it results in them not turning in or completing an assignment. In A Mind of its Own, one of the subjects the author, Cordelia Fine, Ph.D., discussed is people’s tendency to credit themselves for successfully completing tasks, but not recognizing their role in their failures to meet goals or deadlines. This repeated failure to estimate the time or ability needed to finish an assignment is attributed to a theory aptly titled, Planning Fallacy.

Fine cites a study, Planning Fallacy: Why people underestimate their task completion times. In the study, researchers asked students (college) to estimate how long it would take them to complete a task they had been assigned. Many of the students did not finish in time. When asked why, the students blamed events outside of their control. When probed about incidents in their past where they missed assignments of a comparable nature, they also blamed events.

To be fair, college students aren’t the only people who do this. I would argue that even though many people look down upon this behavior in others, we are all guilty of behaving this way. Taking the route of blaming circumstances often allows us to view ourselves in a positive light and not be too hard on ourselves when we do fail to meet our obligations. Yet taken too far it leads to underachievement and being characterized as a misfit or a ne’er-do-well: a person who can never get anything done, either well or at all.

Even when you are pretty good about meeting assignments or in a profession where slip-ups aren’t tolerated, planning fallacy can also affect you in a negative way.

For example, as a professor I take my 'craft' seriously, sometimes to my detriment. As I like to never be bogged down with papers, exams, etc., I start grading assignments as soon as they are turned in. Since I am pretty quick in grading them I have a short turnaround time. Due to my quick turnarounds I became overconfident (in my early days as a professor). I sometimes promised to return assignments in a couple of days as opposed to providing myself with a week or two.

A few times this led to feverish grading for no other reason than to maintain a promise. Although my students may not believe it, events also come up in my life that make returning grades to them difficult. Yet, I knew my credibility would suffer if I provided an excuse, so I forged ahead and completed my tasks. However, I could have avoided these situations by simply giving myself an additional day or few days for emergencies before promising such quick returns.

Final Thoughts

Time-management is a concern for the chronically unprepared and the consistently ready. Regardless of one’s work habits, allowing for unplanned contingencies will help the always late to be on time and help keep the always on time from overburdening themselves trying to meet a deadline when the unexpected occurs. Factoring in room for the unknown can benefit all.

Pop PsychologyBakari Akil II, Ph.D. is the author of Pop Psychology - The Psychology of Pop Culture and Everyday Life! You can also check out his page on Twitter.