Kanban vs Scrum Myths and Hype

http://blogs.versionone.com/agile_management/2012/01/06/1-kanban-vs-scrum-myths-hype/

Recently, I heard folks at a few of my clients and at a couple conferences talking about why they are considering moving to using Kanban vs. Scrum.  I have no preference to either method other than choosing the right agile development tool for the job.  My concern derived from what I have heard identifies the beginnings of some myths and also demonstrates some of the hype around Kanban.

First, a clarification; Kanban with a capital (K) is the term David Anderson coined with respect to an agile development approach to driving change based on lean principles.  Kanban with a little (k) represents the idea of the “sign” or “billboard” that provides the signal/visibility in a production line for additional demand for service of a particular station. It is one of the tools that enables just-in-time (JIT) action as described in the Toyota Production System.

Kanban, as Anderson explains in his book, relies on change occurring in more of an optimizing manner (see kaizen culture).

David Anderson’s Kanban book

This is the significant difference between Kanban and Scrum.  In a Kanban approach, an organization can begin with their current practices with a few exceptions. Kanban requires:

  1. A high degree of visibility into the state of all work queued and in progress
  2. Absolute respect for WIP limits
  3. A commitment to execution in a ‘pull-based’ manner from the prioritized work queue

Kanban also demands a focus on quality.  In fact, this is Anderson’s first step in his six-step recipe for Kanban.  Quality comes first primarily because of the obvious cause-and-effect relationship to waste — and because it’s generally more in the direct control of technical management.  Working down his recipe, there tends to be less control and influence over the changes by technical management.

Now for the Myths and Hype

Myth:  Scrum has work pushed onto the team while in Kanban work is pulled into the system.  This is incorrect.  Scrum does not have work “pushed through the system.”  It is a pull-based agile development system with work pulled in larger batches (the Sprint Backlog).  A Scrum implementation (as well as Kanban) becomes a ‘push-based’ system when the business doesn’t respect the current proven capability of its teams to produce value and just continues to push demands for service into the system.

Doesn’t just apply to Kanban

Hype:  Kanban at its core is summarized by the premise:  ’Stop Starting, Start Finishing’. The entire team’s focus is on ‘getting to done’ for the tasks in progress. This statement is certainly true of Kanban, but the implication that Scrum does not have this focus is not true.  Scrum done right has the same focus, delivering software sooner and doing so in priority order to maximize the value delivered to the customer. I’ve coached to Scrum teams for years that, wherever possible, everyone on the team should work on the highest priority item and get it done first before starting on the next item in the Sprint Backlog.  This implies limiting WIP, as well as focusing on delivering the Backlog in rank order.

If the focus of a Scrum team is to just get everything in a Sprint Backlog into an in-progress state, regardless of priority, then you have a dysfunctional team that’s most likely not working cross-functionally and certainly not focused on delivering the highest-value items first.

Hype: The statement, “The Kanban method is intuitive and is quickly and easily adopted by teams,” to me is a statement that’s used irresponsibly.  It is too often a battle cry of those trying to sell Kanban as a product.  It is the cop-out reason used by many organizations who are failing at Scrum and looking at Kanban.

In Part 2 of this post we’ll continue the conversation about implementing Kanban and some of fundamentals that hold back Kanban and Scrum implementations.

 

 

n the first part of this postwe established a context about Kanban as an agile software tool (not to be confused with the manufacturing term, kanban).  I also explored some of the key myths and hype behind Kanban vs Scrum.  Now I’ll discuss the realities of implementing Kanban and some of the fundamentals that hold back both Kanban and Scrum implementations.

On paper, Kanban is certainly easier to kick-start from a change management perspective because you can leave current roles and processes largely intact; you just need to get commitment from the business to adhere to three basic principles:

  1. Provide a high degree of visibility/transparency of the state of all work queued and in progress
  2. Establish and respect WIP limits in the value flow
  3. Commit to execution in a ‘pull-based’ manner from the prioritized work queue

Yeah, just get commitment and practice of these three things… Much easier said than done in my experience because they are frequently outside the circle of influence of those driving the change to implementing Kanban!

Usually it isn’t that the agile software teams are unable to execute under Scrum; the fundamental issue is that the business isn’t willing to accept a “pull-based” execution model  (required for Kanban and Scrum).

Businesses continue to make irresponsible commitments to customers and investors. This only perpetuates crystal-ball thinking, fixed-date, fixed-scope and fixed-cost projects. It’s the classic sales-driven model we see all too often where the sales arm doesn’t respect the capability of its product development group to produce predictable value for the customer in a timely manner, and with an agreed-upon level of quality. After all, quality is a business decision.

This irresponsible action ends up causing organizations to be unpredictable in their delivery, have lower quality, and to burn out their teams.  These outcomes in turn destroy brands, ruin company reputations on Wall Street,  increase the percentage of each investor dollar serving up technical debt (in lieu of adding new value to products), and causes instability in the organization’s systems due to turnover.

Bottom line, if an organization can’t make the commitment to respect their product development system’s proven delivery capability at the current level, neither Kanban nor Scrum will provide predictability.  But even in the face of this dysfunction, agile methodologies like Kanban and Scrum can still provide faster learning to teams, which allows them to test their assumptions faster and provide more value to their customers by delivering what they actually need.

In conclusion, I leave you with this advice:  ignore the myths and hype about Kanban. Before you can make any decisions on the Kanban vs Scrum debate, you must first evaluate:

  • Your organization’s product development and sales culture,
  • The nature of the demand for service from product development,
  • The competency of your organization to plan and execute change, and
  • The degree to which you’re willing to face the truth

Only then can you choose the best agile software tool for the job.

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