Complexity Is Exponential

Every case in Module 4 shares a structure: small problems interacting. Interaction is multiplication, not addition. Add a stakeholder group and you do not add one relationship; you add one relationship with every other group. That is why complexity is exponential.

“The greatest shortcoming of the human race is our inability to understand the exponential function. We live in a world that can change exponentially, but we have brains hardwired to plot things out linearly.”

We saw it collectively during the early weeks of the COVID-19 pandemic, when doubling times were public knowledge and still consistently under-read. We see it in compound interest, in population and resource curves, and in the way technology adoption S-curves catch incumbents out.

“If you ask me what is the worst thing in the world, I will say it is compound interest.”

The standard approach: list the risks, estimate likelihood X, estimate impact Y, multiply X by Y. Then build a table of thirty, sixty, ninety risk factors and score them all.

“When the risks you anticipated happen, they become issues. When the risks you didn't anticipate happen, you become a former project manager.”

• A register scores risks individually; failure comes from their combination.
• It grows without limit, and past a certain size nobody reads it.
• It gives a comforting appearance of control while the interaction effects go unmeasured.
• It says nothing about whether this organisation can cope with this project.

“As complexity increases, the cost of managing the complexity increases at an exponential rate until the system finally collapses.”

Complex projects are vulnerable to tipping points: conditions that, once crossed, cause system behaviour to change radically. Terminal 5 crossed one at around 6am. LAS crossed one within an hour of go-live. TSB crossed one during the cutover weekend. Before the tipping point, everything looks recoverable. After it, nothing does.