I’ve started going back and reading papers by Kahneman, et al, to avoid the depression that set in after finishing Kahneman’s book, “Thinking, Fast and Slow“. I’m currently reading the 1977 paper on “Intuitive Prediction” and from page 2-2:
“The planning fallacy is a consequence of the tendency to neglect distributional data, and to … [focus] on the constituents of the specific problem rather than on the distribution of outcomes of similar cases.” [emhpasis added]
This directly supports the recommendations in Kanban with respect to collecting data and using statistics (including Control Charts, see Benjamin Mitchell’s description from 2009 and this article on more charts in Kanban), which came up again on the Kanban-dev list. If you read Pablo Emanuel’s response, you can see the connection with The Planning Fallacy:
“The blockage may … or may not … be there in the future. The best way to understand which is which is to look at the whole distribution…, instead of trying to look only at averages.”
So, even if you think events are “unlikely”, you should still capture the blockage data (timing and cause) so that it will help your future forecasting because you’ll have better distribution data.
p.s. See my new T-shirt design: “The Planning Fallacy”. Take a look here.