Project Management Scott Johnson Project Management Scott Johnson

Agile vs Waterfall

A social media debate over SpaceX and “the good ole days” of government mega-projects sparked this breakdown of Agile vs. Waterfall project management. From surgical robots to rocket landings, learn which approach fits innovation—and which one still uses floppy disks.

I got into an interesting “debate” on social media today. A guy criticized SpaceX for having yet another problem with a Starship launch. They’ve only launched about a dozen, several intentionally blown up as part of the test cycle. But sure, let’s go ahead and call that a failure, just to humor the guy. Then he led into something about needing more “Werner Von Brauns” (the NAZI scientist we paperclipped and was certainly responsible for the deaths of a lot of British civilians) - and admittedly the guy was probably talented, but he also had about 50,000 people on the project and unlimited taxpayer resources. Versus, SpaceX is a scrappy team and is privately funded. Werner wasn’t landing rockets back on the launch pad. Werner wasn’t putting 60,000 privately-owned satellites in orbit. Just sayin…

He then launched into a monologue about how great the “good ole days” were—when we spent billions over decades on government-led, waterfall-style mega-projects with 25,000 people on the payroll, giving us space trucks that could barely limp into Low Earth Orbit (for a flight cost of $500 miillion PER DAY). And, by the way, some of those “really” exploded—with astronauts on board.

And that, my friends, is how we slid into the classic Agile vs. Waterfall debate.

Waterfall: The Department of Predictable Outcomes

Waterfall project management works when the path is clear, the requirements are well understood, and you need a fully operational product from day one. There’s no room for "we’ll figure it out later" when the thing needs to work out of the box.

Examples:

  • Accounting Software:
    We know what it needs to do. You can’t file a 2025 tax return if the depreciation module is scheduled for Phase 3 in 2028. The IRS doesn’t do Agile.

  • Surgical Robotics:
    A "patch in the next release" doesn’t fly when the scalpel is in motion. Precision matters. Bugs are bad. Really bad.

  • Aircraft Avionics:
    You don’t want a beta version of your instrument landing system. “Coming soon: Autopilot!” is not comforting at 30,000 feet.

Waterfall shines when you’re refining, not inventing—when lives, laws, or livelihoods depend on everything working exactly right, the first time.

Agile: The Art of Getting There Fast by Being Wrong First

This is where our argument picked up steam. SpaceX manages Starship like an Agile development shop strapped to 33 Raptor engines. They’re not building a rocket—they’re building an entirely new category of reusable spacecraft that will fly for about $2 million per launch, compared to the Shuttle’s $4 BILLION per launch.

The mission?

  • Launch a cruise ship into orbit.

  • Detach the booster, send it back through the atmosphere.

  • Catch it—literally—with giant robotic chopsticks.

  • Set it gently back on the launch pad like a toddler placing a juice box.

Let’s be real:

  • No one knew what the software should look like. They had to invent it as they went.

  • There was no spec sheet for “catch a 300 foot-long skyscraper weighing 200 tons and falling from space with robot arms.”

  • No one had packed dozens of satellites into a bay and flung them out like a train of synchronized UFOs.

  • No one had ever launched a Tesla toward Mars to prove a point.

This isn’t process refinement. This is science fiction made functional. And Agile is exactly the right tool for the job.

Waterfall: When Your Project Team Wants to Grow Old Together

We can spend 20 years planning a perfect project: writing 10,000 pages of specs, holding 400 day-long meetings with “non-gluten-free” bagels and burnt coffee to interpret them, paying contractors to bid on incomplete designs, and then watching as everything becomes obsolete before the ink dries.

Congratulations. You now own a state-of-the-art floppy disk storage system and plan to integrate it with a fax server.

Meanwhile, Agile teams are shipping, testing, breaking, fixing, and learning—sometimes daily. Two years later, SpaceX is on its 15th working prototype. The waterfall crew is still waiting for the change order approval memo to change from CD-ROM to USB thumb drives.

The Bottom Line

Do you want an iPhone 16?

Or a beige rotary phone bolted to your desk that weighs 12 pounds and dials like it’s angry?

That’s the difference.

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