Kanban 101 - A History - Unfettered Agile

Introduction

Early in my career, I had a team member say, “Scrum sucks. Can we just use Kanban?” And I said, “Let’s give it a shot!” I was impulsive, eager to please, and excited to show off my new self-managing team’s new delivery cadence. And I regret it.

Not because they stopped delivering, nor that it yielded bad results – but because nothing really changed. We still had stand-ups, still needed to refine the backlog, still prioritised retrospection, and were still (technically) sprinting in step with the other verticals. I tracked metrics differently, made things more lean, but in the end, nobody felt like anyone was upholding their end of the deal. What the team wanted was vastly different from what I could offer because none of us understood what “Kanban” actually was.

It was a growth moment. I’m more careful now.

Now when I find a new tool, I obsess over the details – its history, theory, and application – before I adopt it. However, I know that digging deep isn’t always an option for everyone. Given how regularly I encounter misconceptions on the topic, I figured I’d share what I’ve learned about Kanban, and hopefully pass down some lessons about how to effectively apply it.

This article will focus on the history of the methodology – which starts with cars.

A Weird Place to Start

Ford Motor Company wasn’t the first consumer car brand at the turn of the century, but it quickly became the most popular. With a price tag of $260 (roughly £3700 today), the price was difficult to beat. Ford’s plants famously used a rolling assembly line. The car was assembled on a long conveyor belt, passing teams whose job was to install specific pieces,¹ reducing the manufacturing time per car from 12 hours to an hour and a half.² Early days, cars were flying out of the factory as fast as they were made, and shipped worldwide.

This was possible because of the size of the factories, the massive resources at their disposal, and a demand keeping lockstep with America’s urban growth. This success allowed Ford (and other American brands) to dominate the passenger car markets internationally – which made it difficult for little startups like Toyota to compete.

From Looms to Cars

In 1924, after years of prototyping, Sakichi Toyoda released the first automatic loom to the world, putting his little company “Toyoda Automatic Loom Works” on the map.³ Not one to stop innovating, he sold the patent to invest in his son Kiichiro’s vision of developing automobiles to compete with Ford and GM.⁴ Toyota released the G1 Truck in 1935, the Model AA passenger car in 1936, and established Toyota Motor Co. in 1937.⁵ ⁶ Rising global tensions, and the desire to spur domestic innovation inspired the Japanese government to block the import of American vehicles, giving Toyota an opportunity to grow.⁷ While the AA was never as popular as passenger cars from Ford or GM, in its time only selling up to 1404 cars,⁸ it was the first step in Toyota’s journey to becoming the giant it is today.

War with China

Japan’s ongoing war with China culminated in a full-scale invasion in 1937, as they entered World War II. War needs vehicles, and Toyota had debts to pay from its R&D. They paused development of passenger cars, and spent the bulk of WWII making G1 trucks for the military instead.

The thing is – manufacturing facilities are excellent bombing targets, and by the time Japan surrendered, Toyota’s factories were wrecked.⁹ They resumed producing vehicles in 1947, but with massive supply chain issues and an economy in shambles, Toyota couldn’t make ends meet.¹⁰ The company was bailed out in 1949, under the condition that management work with the labour unions to implement concrete proposals for cost reduction without cutting any jobs.¹¹

Where Ford had factories, resources, and demand, Toyota had none – yet still needed to keep the lights on. A tall ask.

Inventory Overflow

Toyota limped along for several years, bolstered again by military contracts for the Korean War, but eventually faced issues with an inventory system that couldn’t economically scale. Parts were being machined and delivered that weren’t needed, or the parts that were needed weren’t always on-hand, leading production delays, and manufacturing spaces overflowing with assemblies waiting to be installed. This necessitated a new way to think about managing inventory as a way to substantially reduce costs.¹²

Signals and Supermarkets

“Giant Can Bean” by rooneg is licensed under CC BY 2.0.

Let’s consider how a supermarket manages inventory, as Taiichi Ōno did when he was tasked with solving Toyota’s manufacturing crisis.

A shop owner has a display with 5 cans of beans. When the shelf is empty (or nearly empty), it is a signal to the shop owner to restock the display. She has 50 more in the inventory, but the shelf only has space for 5. When her inventory runs low, she may order more – but never more than she knows she can sell. At the same time, the customer will never pull more cans of beans than they need. These signals result in a steady, consistent, predictable flow of beans from inventory to customers without unnecessary overhead.

Toyota looked to apply this concept to inventory management processes with great success. The assembly teams would now request the parts only when they needed them. If there’s an effective flow (remember this word) of parts through the system, the inventory team can restock when needed.¹³ Predictability improves, and so does productivity.

Spit shine the details, and track request tickets on a physical board for transparency, and this method became known as Kanban.

Kanban in Software

File:Simple-kanban-board-.jpg — “Simple-kanban-board-” by Jeff.lasovski is licensed under CC BY-SA 3.0.

Most people today know Kanban as a methodology for software project management, popularised by David J. Anderson’s book “Kanban: Successful Evolutionary Change for Your Technology Business” outlining the details of implementation, using case studies from previous projects he’d run with Microsoft, and more has been published on the topic since.

Building software is different from building a car, but Anderson shares plenty lessons about managing throughput. Our collection of Not-Done tickets are analogous to requests for usable parts to contribute to the product under construction. We develop only what’s needed when it’s requested, never anything extra. His work has had a huge impact on software development strategy since – for better or for worse.

Conclusion

Toyota dragged itself out of insolvency through adherence to the Kanban methodology, and with a cumulative total of 300 million cars, is now the largest car manufacturer in the world.¹⁴ There’s no question about whether Kanban works – it’s just a case of how you apply it.

As a tool for software, Kanban has become a very popular “alternative” to other Agile frameworks, and is sometimes referred to as an Agile framework of its own (which I take issue with). But in any case, in the last 15 years it’s become a staple term in the software industry’s vocabulary, whether it’s implemented effectively or otherwise.

In the next article, I’ll explain the theory of Kanban as a software development framework, and ways that it can be applied to your delivery strategy.

Sources:

Kanban 101 – A History