Is there really a project "continuum"?

What continuum?

“In theory, theory and practice are the same. In practice, they’re not.” Albert Einstein

“Just because it moves in circles doesn’t mean it’s a life cycle. It could just be spinning its wheels.” Unknown

I’ve been in project management long enough to see trends come, go, and occasionally get repackaged as something “new.” But there’s one slide that seems to survive every reboot: PMI’s project life cycle continuum.

It shows up in training decks, conference talks, and certification prep courses—the tidy little spectrum:

Predictive → Iterative → Incremental → Agile

A clean progression, implying that each step represents a more advanced, more flexible, more enlightened way to run a project.

And yet, every time I see it, the same question comes to mind: Are iterative and incremental really life cycles… or are we just giving delivery tactics a promotion they didn’t earn?

Let’s look at that.

Predictive is a full life cycle. It includes comprehensive planning, scope definition, linear execution, and structured closure. It addresses all aspects of project management—from stakeholder alignment to risk mitigation—within a well-defined governance framework.

Agile, as defined by PMI, is also a complete life cycle. And here’s the nuance that often gets missed: Agile isn’t just “next on the spectrum.” It’s an umbrella term for any adaptive approach that is both iterative and incremental. It includes formal methods like Scrum, Kanban, SAFe, and custom hybrids—as long as they deliver value frequently, embrace change, and involve stakeholders continuously.

In PMI’s own words, agile is: “both iterative and incremental to refine work items and deliver frequently.”

So far, so good.

But that leaves iterative and incremental standing alone on the continuum—as if they, too, are complete life cycle models. That’s where things start to fall apart.

Iterative approaches are designed to refine a solution over time. You build a version, gather feedback, adjust, and repeat. It’s excellent for situations where you’re converging on an uncertain solution—but it doesn’t guarantee usable output early, and it offers no structure for managing stakeholder engagement, governance, or closure.

Incremental approaches focus on delivering small, functional pieces of the final product. Each piece adds value. But without iteration, you risk locking in suboptimal decisions early. And like iterative, incremental lacks the scaffolding needed to manage a project end-to-end.

In short, they’re not life cycles—they’re delivery mechanisms. Useful? Absolutely! Standalone? Not without significant support.

Which brings us back to that tidy PMI continuum. It’s a helpful visual, but it oversimplifies a critical distinction. Agile isn’t just a step beyond incremental—it’s where the pieces come together under an adaptive governance model.

So what do you think? Is it time to rethink how we teach and apply these terms—or are we too comfortable with diagrams that almost work?

Coda

I have been playing around with AI for the past couple of months, and decided to ask it to make the meme at the top of this post. It is obviously computer generated, and not nearly as good as what I could have found on the internet, but I wanted to give it a try. What do you think? While I am certain AI will eventually get to a level where it is indistinguishable from humans, it has a way to go.

#ProjectManagement #Agile #PMBOK #DeliveryModels #HybridApproach #PMILifeCycle #Leadership #ProjectExecution #AgileMindset #ContinuousImprovement #PMI