The Importance of Having a Single Backlog
What Lean manufacturing can teach us about backlogs
3 August 2017
Opinions represent those of the author and not of Scrum Alliance. The sharing of member-contributed content on this site does not imply endorsement of specific Scrum methods or practices beyond those taught by Scrum Alliance Certified Trainers and Coaches.
The term backlog is a descriptive and deliberate word in the Scrum lexicon; it hearkens back to Lean manufacturing concepts regarding production flow. To the product owner, the backlog is a list of functionalities that can be produced by a team to create value. In a Lean manufacturing environment, the backlog takes the shape of unfinished raw material at the beginning of a production line. Drawing similarities between the two paradigms can offer insight into best practices with regard to Agile development. In particular, the need for a single backlog for a production system becomes readily apparent.
It is not uncommon to have multiple backlogs in a development environment, but it may be hard to recognize that as the real situation. Within a team, there is often unity of both purpose and backlog. Everyone knows what they should focus on as a group, and they can unify behind a goal. The team has a single backlog, and to some extent that is correct.
When the team reaches outside for external assistance, though, things can change. Requests go unheeded. Responses are slow. Deadlines are missed. The reason for this is simple: The external group has a different set of priorities than yours. In other words, they have a different backlog.
From a Lean perspective, imagine what this would look like on a production floor and you can see how gridlock could occur. Picture a number of production machines that would take an input and form an output. Optimally, each machine would have one input and one output. That is a sign of a single purpose and backlog. New backlog always starts at the beginning of the line to be queued up and prioritized. What would happen if any machine’s output could lead into any other machine’s input? What if work could start anywhere and be initiated by any other machine or person? The only mitigation would be each individual machine’s priority. Gridlock would soon result as priorities conflict.
Lean thinking was created to combat inefficiencies within the manufacturing world. Backlog management in a manufacturing plant is key to speed and quality development. It goes without saying that the purpose of a manufacturing line is a single purpose.
Yet having multiple purposes and directions is exactly what we might do in business. Groups interface with each other to deliver and receive dependent work. Each time they interface, the unspoken priorities of the group dictate what will be done next. How is it handled in a multi-priority environment? Teams wait. They elevate to management. They play politics. After all, isn’t their work the most important? Their pay raises depend on what they produce, not on what other teams produce. Thus we enter into a fierce competition for resources, resulting in deadlock.
Current rating: 4.3 (3 ratings)
The community welcomes feedback that is constructive and supportive, in the spirit of better understanding and implementation of Scrum.