Identifying impediments through flow metrics

Flow metrics reveal process problems before they cause significant delivery delays. Teams skilled in metric interpretation can spot issues early before they become crises.

Several common patterns in flow metrics reveal specific impediments that teams should address:

• The "expanding WIP" problem appears as rising cycle times and decreasing throughput despite consistent team capacity. This indicates teams starting too much work simultaneously, causing context switching. The solution is to implement WIP limits that match team capacity.
• "Bottleneck bounce" shows in Cumulative Flow Diagrams as alternating widening bands. Work piles up in one state, gets addressed, then backs up elsewhere. This reveals resource imbalances or dependencies between specialists. Cross-training and swarming help reduce these bottlenecks.
• "Queue bloat" appears as growing lead times without corresponding cycle time increases, happening when backlogs grow faster than completion rates. Regular backlog refinement and clear prioritization policies address this issue.

Some metric changes can be misleading. For instance, cycle time might increase when teams implement quality improvements or address technical debt, which is a positive investment rather than a problem. Context remains crucial when interpreting metrics.