When I was preparing to interview Robert McLean, co-author of “Bulletproof Problem Solving,” I didn’t expect to end up talking about trees and solar panels.
The book is co-written with Charles Conn, and it turns out that trees are central to its problem-solving method. Thanks to the magic of the trees, those solar panels are now on McLean’s house.
McLean and Conn worked at the global consulting firm McKinsey & Company, where they practiced professional problem-solving for decades.
Logic trees, or decision trees as they’re sometimes called, help people to break down a problem into its constituent parts and predict the outcomes of several possible actions.
The “trunk” is the central problem or decision that needs addressing. From there, you write down the impact of different decisions. It’s these points, and their implications, that make up the “branches” of the tree.
Written down, it becomes easier to compare options and determine the best way forward.
“Charles and I still find ourselves drawing a lot of trees,” McLean admits. “It’s an iterative process, and it takes a while before you get to the logic structure that’s going to serve you best.”
So how do you start?
Building Your Tree
“If you’ve got a new issue, or a problem that you’re reasonably unfamiliar with, you’re normally going to start by asking, ‘What are the main levers here that are behind the problem?’ Is it a market-share problem or a pricing problem? Is it an investment problem or an innovation problem?”
“So, your first cut of the logic tree may simply be to lay out what the contributing factors may be,” he says.
As you dig deeper, different routes to a solution emerge. Your tree grows and changes shape. You can also work backward, too, which brings us to the solar panels.
When considering installing solar panels on his home, McLean had to work out if it was worth it – a difficult prospect with so many different factors at play. Fortunately, he solved this dilemma with a logic tree.
McLean started at the end (“I should put solar panels on my roof now”) and worked his way backward.
“I started with that conclusion, or recommendation, and then said, ‘What would I have to feel comfortable about in order for me to go ahead with that solution?'” he recalls.
He narrowed it down to three major considerations: first was the financial proposition – whether the energy savings would outweigh the cost of installation; the second was the solar panel market – if the price of panels was likely to fall, perhaps it would be best to wait; and third, McLean considered the environment. Would the reduction in his carbon footprint be significant enough to warrant the investment in solar panels?
By starting with an end position and following the logic backward, McLean figured out how to proceed.
“It turned out that the payback, in my case, in Australia, was less than five years, that the delay really wasn’t worth waiting for, and that the impact on the carbon footprint was quite significant. So that led me to conclude that it made sense as an investment,” says McLean.
How to Make the Best Decisions
In their book, McLean and Conn present wide-ranging examples of logic trees. They also explore other ways to make informed decisions, particularly espousing the merits of collective problem-solving.
For example, they recommend removing hierarchy from decision processes as much as possible.
“We find good leaders do this very well,” says McLean. “There may be a dozen people in the room and they’ll go around the room and let everybody talk, and then they will speak last. Whereas, if the leader starts with his or her view at the beginning of the problem-solving meeting, that has a huge impact on the responses that come as you go around the table.”
In our interview, McLean also discusses a version of Multi-Voting. Having collaboratively come up with a number of ideas, he might give his team 100 votes each. They’d then distribute these votes among a number of possible solutions to a problem.
“That democratizes the process, and even quite junior people on the team are given a voice,” McLean points out.
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