Flow efficiency
Flow efficiency is the ratio of value-add time to total elapsed time for a case — typically expressed as a percentage. A case that took 5 days end-to-end but only 4 hours of actual work has 10% flow efficiency. Most knowledge-work processes have flow efficiency below 15%; world-class operations approach 40%.
Flow efficiency is the metric that surfaces where to focus: a 10% flow-efficient process gets 90% of its calendar time spent waiting, not working. Doubling work speed produces marginal gain; halving wait time doubles throughput. The remediation patterns: reduce handoffs (each one introduces wait), limit WIP (work waits less in less-congested systems), and design for asynchronous communication (no waiting for a meeting). Tracking flow efficiency requires distinguishing 'in-progress' from 'waiting' in the workflow — most ticket systems lump them together, so the metric usually requires deliberate instrumentation.
Related terms
- Cycle time
Cycle time is the elapsed time from when work starts on an item (first commit, status change to In Progress) to when it ships to users.
- Value stream mapping
Value stream mapping is the Lean technique of drawing a current-state diagram of a process — every step, every queue, every handoff, with cycle time and wait time labelled — to identify where value is being added and where it's not.
- WIP limit
A work-in-progress (WIP) limit caps how many items the team can have in flight at once, per workflow stage.