The almost inevitable outcome of "now knowing what you don't know" is wishful thinking. Even the use of benchmarks may not help.
Wishful thinking is one of the curses of project management. Any project team without a good knowledge of the challenges that they will face in a project, tend to underestimate them. They assume things will work well, they assume the “best case scenario”, and they end up with an over-optimistic view of the project, an over-optimistic view of costs, and an over-optimistic view of schedule.
Daniel Kahneman gives a great example of this in his book “Thinking,
Fast and Slow”.
He describes a project, many years ago, where he convened a
team to design a new high-school curriculum and to write a textbook for it
(ironically, it was about judgement and decision making). They had had several team meetings to
construct an outline of the syllabus, had written a couple of chapters, and
even run a few sample lessons. They
decided to do some planning, and to create an estimate of how long it would
take to submit the finished draft of the textbook. Kahneman knew that one of the
most effective ways of estimating is not to start with discussion, but to get
everybody to individually submit their judgment, so has asked everybody to
write down their estimates, and then collected these in. Estimates ranged from 1 ½ years to 2 ½ years
with a median of two years, to finish and submit the first draft.
Then he had another bright idea. He asked one of the
curriculum experts on the team whether he could think of any examples of similar
projects in the past, and how long they had taken.
“He fell silent” Kahneman writes. “When he finally spoke, it seemed to me that he was blushing; embarrassed by his own answer: ‘You know, I never realized this before, but in fact not all the teams at a stage comparable to ours ever did complete their task. A substantial fraction of the teams ended up failing to finish the job’”. That fraction was 40%.
Kahneman then asked how long it took those who actually had
finished the job.
“I cannot think of any group that finished in less than seven years” he replied, “nor any that took more than 10”.(Note that this guy himself had, shortly before, estimated it would take about two years!). Then Kahneman asked how the current team ranked compared to the others; perhaps they were much better and could finish much faster! “We are below average” he replied “but not by much”.
So now the team had new knowledge, that comparable or better
teams often fail at this job, and those that succeeded took four times longer than the group's
estimate.
So what do you think the group did?
Kahneman tells us
“Our state of mind when we heard Seymour is not well described by stating what we “knew”. Surely all of us now “knew” that a minimum of seven years and a 40 per cent chance of failure was a more plausible forecast than the numbers we had written on a slips of paper. But we did not acknowledge what we knew. The new forecast still seemed unreal, because we could not imagine how it could take so long to finish a project that looked so manageable. All we could see was a reasonable plan that should produce a book in about two years. ………. The statistics that Seymour provided were treated as base rates normally are – noted and promptly set aside. We should have quit that day. None of us were willing to invest six more years of work in a project with a 40 per cent chance of failure ….. After a few minutes of a desultory debate, we gathered ourselves together and carried on as if nothing had happened”.
The book was eventually finished eight years later. The initial enthusiasm for the idea in the
ministry of education had waned by the time the text was delivered, and it was
never used.
...
This is a very interesting story. Not only did the group not know what they
didn’t know, they were unable or unwilling to accept the new knowledge when it
was presented. They ignored it, and
continued with the wishful hope that they would be finished in two years.
Kahneman concludes from this that there are two different
approaches to forecasting; the inside view and the outside view. The inside view is based on “what you know
that you know”, and what the team knew was that they had made some good
progress already, albeit completing some of the easiest chapters at a time when
enthusiasm was at its peak, and they extrapolated from this good progress.
But they didn't know what they didn't know, and they didn't foresee the bureaucracy, the distractions and the conflicts that would eventually arrive. However because they were anchored to their inside view, they would not accept the outside view, even though the outside view was based on reliable baseline statistics.
But they didn't know what they didn't know, and they didn't foresee the bureaucracy, the distractions and the conflicts that would eventually arrive. However because they were anchored to their inside view, they would not accept the outside view, even though the outside view was based on reliable baseline statistics.
The rest of Kahneman’s book, which I highly recommend, explores
other aspects of the psychology of decision-making, and gives many examples of
how people will make wrong decisions as a result of over confidence through
limited data.
There are many are implications here for knowledge
management; the need to access outside knowledge through activities such as peer assists, the need to
collect baseline data on performance to act as a “reality check” for optimistic
teams, and the need for continuous project learning to recognise when
predictions are optimistic, and to renegotiate the prediction.
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