Limits to Growth

A systems archetype describing how when a growing system encounters a novel constraint that slows growth, it is tempting to double-down and invest even more resources in what led to past growth, when what’s really needed is to divert resources to understanding and avoiding this new constraint. Often the new constraint is caused by past growth, making further growth the precise opposite of what’s needed. This is another classic example of how systems often defy our intuitions about them.

“The Limits to Growth” is also the title of a landmark report published in 1972 by Donella Meadows and a global consortium of scientists describing “the predicament of mankind,” that our species is fast approaching a global limits-to-growth constraint: that unless our species takes steps to curb the rate at which we’re exhausting the planet’s resources, “the most probable result will be a rather sudden and uncontrollable decline in both population and industrial capacity.”

Examples

Consider an important software project with lots of people working on it. Early on, adding more people to the team seemed to accelerate progress. But as communication overhead, technical debt, and other costs of complexity (constraints) begin to accrue, progress slows. So the project managers ask for more engineers to speed things up again, which only slows things more since there are more coordination and complexity costs that everyone on the team incurs. Fred Brooks in The Mythical Man-Month summarized the situation in what has come to be known as Brooks’s Law: “adding more people to a late software project makes it later.”

Systems in this state share a common structure: a reinforcing feedback loop driving growth, and a balancing feedback loop slowing it due to some constraint:

Notably, performance or growth of the system is an element of both loops, both driving and hindering growth until the constraint is eliminated.

Strategies

• Ideally, analysis of the limits of growth is best done before encountering those limits. When your organization is growing, ask yourself what pressures might be building up as a result and consider how to relieve them.
• If you’re already encountering limits to growth, be willing to divert resources to discovering, understanding, and working within those limits. Remember that growth was already slowing due to these factors, and resist the idea that growth is slowing because of this diversion of resources toward sustainability.
• At least in the realm of software projects, I’ve found that you can sometimes avoid the limits to growth on a system by splitting it into multiple systems (or, with foresight, building more, smaller systems to begin with). Of course, this can bring with it new problems dealing with the increased complexity of the aggregate system, which can perhaps be divided again, and so on.

Further Reading

• Using “Limits to Success” as a Planning Tool by The Systems Thinker