Moving toward the target condition |
Both Scrum
and Kanban use visual boards to show available work, work-in-process, and
completed work (often under the headings “To-do”, “Doing”, and “Done”). Scrum
and Kanban encourage and promote team-based problem solving throughout the completion
of prioritized tasks, and can be effectively adopted in both software- and
hardware development, as well as in project-based production environments, such
as in ETO manufacturing.
In Scrum,
tasks are selected from a prioritized backlog and posted under “To-do”. The
tasks that are selected are expected to be completed by the Scrum team during
the sprint that follows, which
typically takes place over the next 7 days to 4 weeks (Sprint duration is normally
constant from one sprint to the next). Each day during the sprint, all team
members gather around the Scrum board in what’s known as a stand-up meeting
(typically maximum 15 minutes long). During the stand-up, the participants
discuss what was achieved on the previous day, the plan for today, and the
problems that were addressed / remain to be addressed such that the Sprint can
be completed on time. On the first stand-up meeting, individuals will select and
move “To-do” items to “Doing”. Upon completion, these jobs will be moved to
“Done”. On the last day of the Sprint, team members should reflect on the
Sprint in order to improve during the subsequent Sprint. In essence, Scrum
constitutes a pull-mechanism as the quantity of tasks that is released into
each Sprint remains fixed for the duration of the Sprint. The quantity of tasks
released is based on the amount of required capacity that is anticipated to
complete each task during the Sprint. No further tasks shall be released into
the current Sprint unless there is a plausible exception, and only then by
approval of the product owner.
Kanban
is very similar to Scrum in that a visual board and daily stand-up team
meetings are the mechanisms for success. However, the major difference is that
a Kanban board explicitly limits the amount of tasks that can be assigned to each
stage of the operation. In the case of Kanban, “Doing” is often segregated into
separate operations, each with a visually-defined limit of tasks that can be
processed simultaneously in that operation. Tasks are still selected from a
prioritized release list, as in Scrum (and indeed POLCA and CONWIP). Yet the
fundamental difference between Kanban and Scrum is that Kanban can be more
reactive to changes in requirements. This is due to the fact that tasks are not
locked in for the duration of the sprint (e.g. 7-28 days); the response time of
a Kanban team is the time it takes for capacity to become available after
having completed a current task in process. This follows the general principle
of one-out-one-in, as in CONWIP. |