What is Cadence?
Mark Stringer gave me some good feedback recently, that I clearly hadn’t described what I meant be Cadence at the recent miniSPA conference. In order to try and correct that, I thought I’d try and clarify with a blog post that it not simply variable length iterations.
The purpose of a cadence is to establish a reliable and dependable capability which demonstrates a predictable capacity. Cadence gives some confidence in the upcoming work when we are triggering rather than scheduling work.
Time-boxing is one specialised form of cadence. It’s like a metronome, giving a single tick. All the main process events are based around this single tick, as shown below where the dotted vertical lines represent the Sprint boundaries. In this example, the unit of work is a User Story, and User Stories should be small enough to be scheduled into a Sprint, and subsequently completed in the same Sprint. Stories in Progress are limited to two, as a good Scrum team might, but Stories don’t always fit exactly into a Sprint. Note also, that while releases can happen each Sprint, User Stories are only potentially shippable product increments.
Kanban on the other hand has a cadence which is more like a drummer. The rhythm is more complex than the single tick of a metronome, and can be more varied, as shown below. In this example, the unit of work is a Minimal Marketable Feature, which while needing to be as small as possible, is not constrained be being required to fit into a schedule. Instead, an MMF is able to flow over a number of process events while it delivers some releasable value. Planning, reviewing, retrospection and releasing all still happen regularly, but they are de-coupled. They can happen independently, at differing rates, which may provide more freedom in creating a natural process which enables the team.
A cadence is usually ‘harmonic’, in that there is a neat overlap between the different rhythms, as in this example. However, it does not have to be. A look at some definitions of cadence can show why. These are some favourites I picked off dictionary.com
- In music, the ending of a phrase, perceived as a rhythmic or melodic articulation or a harmonic change or all of these; in a larger sense, a cadence may be a demarcation of a half-phrase, of a section of music, or of an entire movement
- Music. A progression of chords moving to a harmonic close, point of rest, or sense of resolution.
- The flow or rhythm of events, esp. the pattern in which something is experienced: the frenetic cadence of modern life.
Thus cadence is what gives a team a feeling of demarcation, progression, resolution or flow. A pattern which allows the team to know what they are doing and when it will be done. For very small, or mature teams, this cadence could by complex, arrhythmic or syncopated. However, it is enough to allow a team to make reliable commitments because recognising their cadence allows them to understand their capability or capacity.
- Dew Drop – July 22, 2009 | Alvin Ashcraft’s Morning Dew
- Friday’s Digest #15 (Kanban, Velocity, Community) | Edge of Chaos | Agile Development Blog
- Kanban In Time-Boxes: The Cadence of WIP and Sprints – new ThoughtStream("Derick Bailey"); – Los Techies : Blogs about software, programming and anything tech!
- Engineering Management: Why are software development task estimations regularly off by a factor of 2-3? – Windy Road