Using Velocity Trends To Uncover Hidden Technical Debt
What is Velocity and Why Does it Matter?
Velocity refers to the amount of work a development team can complete during a sprint, measured in story points per sprint. Tracking velocity over time provides insight into the team’s capacity for taking on new work. A downward velocity trend often indicates emerging problems that hinder productivity, including accumulating technical debt.
Technical debt encompasses the implied cost of additional work caused by quick and dirty solutions, outdated and messy code, or other technical shortcuts. As teams prioritize new features, technical debt accrues silently in the background until code quality erodes to the point that it becomes difficult to deliver value. Slowing velocity is often the first warning sign.
Understanding velocity metrics and detecting decay empowers teams to uncover issues before they balloon out of control. Digging into velocity data guides targeted solutions to address the root causes of chronic issues that inhibit sustained team throughput.
Identifying Velocity Decay
Track velocity session-over-session to reveal downward trends. Within each sprint, monitor the following dimensions:
- Team velocity: The overall amount of work the team completes each sprint measured in story points
- Feature velocity: The throughput of specific product areas or teams
- Defect velocity: The number of live production defects reported
If velocity declines sprint-over-sprint, the team is consistently not meeting their committed goals. The Scrum Master can facilitate a root cause analysis to understand why. Signs of velocity decay include:
- Consistently partially completed sprints: Unfinished user stories get pushed back
- Bugs lingering from previous sprints: Defects displace new development
- Inaccurate estimates: Developers fail to account for unknowns
- Unanticipated obstacles: Impediments disrupt predicted throughput
- Chronic overtime: Working extra hours to complete sprints
Just one downward sprint might indicate an anomaly. Consistently decreasing velocity means existing processes struggle to enable the team to meet commitments.
Digging Into the Data
With early warnings from lagging velocity, leadership can dig deeper into the data to pinpoint solutions. Analyze user stories completed each sprint alongside defect metrics to identify problem areas. Review individual developer contributions to surface bottlenecks. Then, work backwards using root cause analysis techniques like the 5 Whys method to uncover sources of friction:
Example Root Cause Analysis
Observation: Team completed 30% fewer story points last sprint.
Why? The checkout feature took twice as long as expected.
Why? There were more defects than anticipated.
Why? The team had to overhaul significant portions to fix bugs.
Why? Technical decisions made years ago created complexity.
Why? Shortcuts were taken rather than architecting flexible solutions.
Root Cause: Technical debt makes modifying the checkout process extremely costly.
By repeatedly asking why, managers reveal the underlying contributors to problems. The team can then formulate targeted solutions.
Addressing the Root Causes
Consider if pervasive issues like accumulating technical debt cause velocity slowdowns. As legacy code ossifies into rigid interdependencies, even small changes require extensive modifications. Teams waste time navigating outdated architecture rather than building customer value.
Strategically allocate resources to pay down technical debt through activities like:
- Refactoring: Restructuring existing code to simplify future feature development
- Rationalizing dependencies: Upgrading outdated libraries and frameworks
- Migrating solutions: Decoupling outdated technology from new features
- Improving test coverage: Adding missing unit and integration tests as safety nets
While tiresome, confronting technical debt proactively lifts the burden on future output and speeds velocity. Determine if systematic process issues also contribute to velocity decay through retrospective analysis. Arm developers with modern tools, streamline workflows, and promote design thinking to boost sustainable productivity.
Improving Predictability Through Continuous Improvement
Velocity reveals early warnings about process deficiencies and technical impediments. To sustain improvements, revisit systemic issues through continuous introspection:
- Retrospectives: Regular check-ins to realign processes with reality
- Action item tracking: Prevent recurring issues through accountability
- Developer exchanges: Promote best practices sharing
- Spikes: Dedicate time for innovation to avoid stagnation
- Automated testing: Add safety nets through composable test building blocks
Process rigor and cutting edge tools empower teams to take on ever more ambitious goals. Using data-driven insights to fuel continuous improvement initiatives enables sustainable velocity as complexity increases.
Putting New Insights into Action
Just as technical debt accumulates when left unaddressed, insights uncovered from velocity analysis fail to provide value without decisive action. Scrum masters and engineering leaders should:
- Socialize findings across stakeholders to secure buy-in
- Outline targeted solutions to root causes
- Construct roadmaps to align priorities
- Install triggers to regularly reassess burden
- Celebrate improvements early and often
Velocity flows from how well leadership equips the team for stability and scale. Sustaining a culture of data-informed decisions accelerates future throughput. Just as diligent refactoring lifts daily productivity, continuous analysis through velocity trends compounds capabilities over time.