Point Lookout: a free weekly publication of Chaco Canyon Consulting
Volume 12, Issue 19;   May 9, 2012: Nonlinear Work: When Superposition Fails

Nonlinear Work: When Superposition Fails

by

Last updated: August 8, 2018

Much of the work we do is confounding, because we consistently underestimate the effort involved, the resources required, and the time required to get it done. The failure of superposition can be one reason why we get it wrong.
Congestion on a U.S. highway

Congestion on a U.S. highway. One common example of the nonlinearity of systems is the traffic jam. At low densities, adding one more vehicle to the stream of traffic has no measurable effect on the speed of the other vehicles. But as density increases, traffic slows, until it reaches a state like the one shown. How can this be? This phenomenon occurs because of interactions between the vehicles. That is, the natural flow rate is a nonlinear function of vehicle density. Photo courtesy U.S. Department of Transportation.

More often than we'd like, our projects are late or over budget. Or we find that the problem we've tackled is much more difficult than we thought. We aren't stupid (though some might argue otherwise), and we aren't trying to gild lilies our build empires (though some might argue with that, too). Still, these things happen with such regularity that there must be an explanation.

Part of the answer might be that much of the work we do is of a nature that our minds have difficulty comprehending. One property that gives us trouble is nonlinearity.

For example, consider the issue raised by Fred Brooks in The Mythical Man-Month. If three people can complete a task in six months, many would suppose that nine people can complete it in two months. We now understand that this belief is unfounded, and that our expectations are rarely met.

To understand why, let's begin by defining linear work. Work is linear when the outcomes are directly traceable from, and scale with, inputs. When work is linear, we can successfully plan the outcomes before we begin, because we can predict the course of the effort. To make linear tasks go faster, we can divide them into parts that we execute in parallel, without risking complication.

For example, two identical, independent assembly lines can produce output at double the rate of one single line, assuming that their supply and delivery chains are also independent. A manufacturing process implemented as independent assembly lines is a linear process.

But In a system that doesn't
obey superposition, the whole
can be different from
the sum of its parts
nonlinear work doesn't follow this pattern. Although most of the work we do in project-oriented organizations behaves linearly in response to small adjustments, the nonlinearities dominate when we scale those adjustments to a size where we expect to derive large benefits. One attribute of nonlinear work that explains this phenomenon is its failure to obey superposition.

In a system that doesn't obey superposition, the whole can be different from the sum of its parts. In such cases, as we apply more and more resources, the yield per unit of resource can decline. In the case of Brooks's mythical man-month, this can happen because of increased need for management and communication, and increased difficulty in scheduling.

But superposition can fail for a wide variety of reasons. For example, when we decompose a problem into parts, and try to work on the parts separately, one task team might require — solely for scheduling purposes — that another task team take an approach that is less effective than it would have taken if it were free to act independently. We can easily generate numerous examples like this that show failures of superposition that confound our expectations.

In three weeks, we'll continue this exploration of the reasons why nonlinear work is so difficult to manage.  Next in this series Go to top Top  Next issue: Handling Heat: I  Next Issue

52 Tips for Leaders of Project-Oriented OrganizationsAre your projects always (or almost always) late and over budget? Are your project teams plagued by turnover, burnout, and high defect rates? Turn your culture around. Read 52 Tips for Leaders of Project-Oriented Organizations, filled with tips and techniques for organizational leaders. Order Now!

Your comments are welcome

Would you like to see your comments posted here? rbrenmhXARWRMUvVyOdHlner@ChacxgDmtwOKrxnripPCoCanyon.comSend me your comments by email, or by Web form.

About Point Lookout

Thank you for reading this article. I hope you enjoyed it and found it useful, and that you'll consider recommending it to a friend.

Point Lookout is a free weekly email newsletter. Browse the archive of past issues. Subscribe for free.

Support Point Lookout by joining the Friends of Point Lookout, as an individual or as an organization.

Do you face a complex interpersonal situation? Send it in, anonymously if you like, and I'll give you my two cents.

Related articles

More articles on Project Management:

Apollo 13 Shoulder PatchFilms Not About Project Teams: I
Here's part one of a list of films and videos about project teams that weren't necessarily meant to be about project teams. Most are available to borrow from the public library, and all are great fun.
Chocolate chip cookiesNine Project Management Fallacies: II
Some of what we "know" about managing projects just isn't so. Identifying the fallacies of project management reduces risk and enhances your ability to complete projects successfully.
Ice on Challenger's launch pad hours before the launchDesign Errors and Groupthink
Design errors cause losses, lost opportunities, accidents, and injuries. Not all design errors are one-offs, because their causes can be fundamental. Here's a first installment of an exploration of some fundamental causes of design errors.
Phoenix caissons being towed to form a Mulberry harbor off Normandy, June 1944Ten Approaches to Managing Project Risks: III
Project risk management strategies are numerous, but these ten strategies are among the most common. Here are the last three of the ten strategies in this little catalog.
Darrelle Revis, cornerback in the U.S. National Football LeagueWishful Interpretation: II
Wishful "thinking," as we call it, can arise in different ways. One source is the pattern of choices we make when we interpret what we see, what we hear, or any other information we receive. Here's Part II of an inventory of ways our preferences and wishes affect how we interpret the world.

See also Project Management for more related articles.

Forthcoming issues of Point Lookout

Filling a form in hardcopyComing July 3: Appearance Antipatterns: II
When we make decisions based on appearance we risk making errors. We create hostile work environments, disappoint our customers, and create inefficient processes. Maintaining congruence between the appearance and the substance of things can help. Available here and by RSS on July 3.
Truth and LiesAnd on July 10: Barriers to Accepting Truth: I
In workplace debates, a widely used strategy involves informing the group of facts or truths of which some participants seem to be unaware. Often, this strategy is ineffective for reasons unrelated to the credibility of the person offering the information. Why does this happen? Available here and by RSS on July 10.

Coaching services

I offer email and telephone coaching at both corporate and individual rates. Contact Rick for details at rbrenmhXARWRMUvVyOdHlner@ChacxgDmtwOKrxnripPCoCanyon.com or (650) 787-6475, or toll-free in the continental US at (866) 378-5470.

Get the ebook!

Past issues of Point Lookout are available in six ebooks:

Reprinting this article

Are you a writer, editor or publisher on deadline? Are you looking for an article that will get people talking and get compliments flying your way? You can have 500 words in your inbox in one hour. License any article from this Web site. More info

Public seminars

The Power Affect: How We Express Our Personal Power
Many The Power Affect: How We Express Personal Powerpeople who possess real organizational power have a characteristic demeanor. It's the way they project their presence. I call this the power affect. Some people — call them power pretenders — adopt the power affect well before they attain significant organizational power. Unfortunately for their colleagues, and for their organizations, power pretenders can attain organizational power out of proportion to their merit or abilities. Understanding the power affect is therefore important for anyone who aims to attain power, or anyone who works with power pretenders. Read more about this program.

Follow Rick

Send email or subscribe to one of my newsletters Follow me at LinkedIn Follow me at Twitter, or share a tweet Subscribe to RSS feeds Subscribe to RSS feeds
The message of Point Lookout is unique. Help get the message out. Please donate to help keep Point Lookout available for free to everyone.
Technical Debt for Policymakers BlogMy blog, Technical Debt for Policymakers, offers resources, insights, and conversations of interest to policymakers who are concerned with managing technical debt within their organizations. Get the millstone of technical debt off the neck of your organization!
Go For It: Sometimes It's Easier If You RunBad boss, long commute, troubling ethical questions, hateful colleague? Learn what we can do when we love the work but not the job.
303 Tips for Virtual and Global TeamsLearn how to make your virtual global team sing.
101 Tips for Managing ChangeAre you managing a change effort that faces rampant cynicism, passive non-cooperation, or maybe even outright revolt?
101 Tips for Effective MeetingsLearn how to make meetings more productive — and more rare.
Exchange your "personal trade secrets" — the tips, tricks and techniques that make you an ace — with other aces, anonymously. Visit the Library of Personal Trade Secrets.