Article - The Best Example To Explain Optimism Bias Phenomenon


As a part of my project management course I frequently have to talk about the estimation-related phenomenon known as "optimism bias". Succinctly stated optimism bias is described as follows:

We as the species of homo sapiens tend to overestimate our abilities required to perform a specific task and underestimate the complexity of the task in question

Usually when one provides his audience with a complicated and slightly boring definition, he has to follow up with a clear, simple and hopefully entertaining example. Throughout my consulting and teaching career I tried using a number of case studies including pretty much every megaproject on this list. However each and every example used has been met with mixed feelings. Sometimes people never heard about the Denver Airport Baggage Handling system and sometimes they failed to see the connection between optimism bias and the overall project failure.

I kinda gave up on finding the best illustration for this phenomenon, until one of my friends told me the following story:

His son has just started going to the kindergarten and he and his wife agreed that he would pick them up from the bus station located not too far from their home. They have also agreed that his wife would give him a call once she was ready to leave the office (kindergarten was located nearby). So at one point of time he receives a call from his significant other stating that he should pick them up at the bus stop in 15 minutes. Being a responsible person he exits his home right away and arrives at the bus station with 5 minutes to spare.

Five, ten, fifteen, thirty minutes go by. No sign of his wife and kid. Finally forty minutes after the expected deadline (sorry for the project management nerd talk) his family exits from the bus ... The following conversation ensues:

H: Where have you been? I have been waiting here for more than half an hour! And more importantly, why did you tell me it would take you 15 minutes to get here?

W: I don't know, that is what the bus company website said. I logged on and it told me that getting from station A to station B takes 15 minutes ...

H: Just the driving time, right?

W: Yes!

H: But did you consider the following tasks:

1.Walk  from the office to the kindergarten

2.Enter the kindergarten and find our kid in a pile of other screaming children

3.Successfully remove him from the said pile

4.Calm him down and convince him to stop crying

5.Put on his rain boots and rain jacket

6.Calm him down and convince him to stop crying

7.Grab him by the hand and make your way to the bus station

8.Calm him down and convince him to stop crying

9.Get on the bus

W: No, not really!

About the Author

Jamal Moustafaev, MBA, PMP – president and founder of Thinktank Consulting is an internationally acclaimed expert and speaker in the areas of project/portfolio management, scope definition, process improvement and corporate training. Jamal Moustafaev has done work for private-sector companies and government organizations in Canada, US, Asia, Europe and Middle East.  Read Jamal’s Blog @

Jamal is an author of two very popular books: Delivering Exceptional Project Results: A Practical Guide to Project Selection, Scoping, Estimation and Management and Project Scope Management: A Practical Guide to Requirements for Engineering, Product, Construction, IT and Enterprise Projects.