Page 46 - The McKinsey Mind

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24 The McKinsey Mind

only uses a lot of energy, but also ties up inventory, thereby unnec-
essarily swelling Acme’s balance sheet. A reduction in curing time
could thus have a double benefit. Not only would it boost Acme’s
profit line, it also would reduce work-in-progress inventory. What
needs to be true to make this feasible? As a first cut, the question
would seem to be whether it is possible to make Grade A thrum-
mats without a full two-week cure. Coincidentally, one of your
team has just read an article in Thrum-mat Manufacturing Weekly
on a new curing process that utilizes special temperature, humidity,
and atmospheric controls and that produces the same or better
results as traditional curing methods.
Excellent! Your team has now found an initial hypothesis that
passed the QDT.* Your next step will be to test your hypothesis
more thoroughly and, if necessary, refine it. To accomplish these
goals, you should now put together an issue tree.
An issue tree is the evolved cousin of the logic tree. Where a
logic tree is simply a hierarchical grouping of elements, an issue
tree is the series of questions or issues that must be addressed to
prove or disprove a hypothesis. Issue trees bridge the gap between
structure and hypothesis. Every issue generated by a framework
will likely be reducible to subissues, and these in turn may break
down further. By creating an issue tree, you lay out the issues and
subissues in a visual progression. This allows you to determine
what questions to ask in order to form your hypothesis and serves
as a road map for your analysis. It also allows you very rapidly to
eliminate dead ends in your analysis, since the answer to any issue
immediately eliminates all the branches falsified by that answer.

*This example is provided for illustrative purposes only. It is not meant as a specific pre-
scription for any company, partnership, sole proprietorship, or any other organization
involved in the manufacturing, curing, delivering, or servicing of thrum-mats. If you are
actually in the thrum-mat business and are reading this, please do your own research.