The Big Picture
Now imagine you are an executive sponsoring a mission critical project. The project will take millions of dollars and consume significant resources. You ask the project manager when the project will be completed. They respond with a date 18 months in the future:
"January 26th, 2023"
Pretty specific, isn't it? What estimation information is hiding in that answer? How many hundreds of smaller tasks with imprecise estimates were aggregated to create that particular answer? Were the smaller component estimates optimistic or pessimistic? Has the project manager added a risk adjustment to each of the subordinate estimates? Have they added a risk adjustment to the final answer? Did they take their best guess and double it?
Executives are rarely ignorant, but they may not have the project management expertise to even know to ask questions like that. A project manager could bury an executive with footnotes and pages of assumptions to better document the context of the answer - but that would likely be overwhelming and not terribly helpful.
What if we could help executive sponsors understand that there is no such thing as a "precise estimate" while still providing an answer to their reasonable question about how long the project will take?