Weighted shortest job first (WSJF)
Weighted Shortest Job First is SAFe's prioritisation formula: WSJF = Cost of Delay ÷ Job Size, where Cost of Delay is a relative score combining user-business value, time criticality, and risk reduction. The highest WSJF item is done next. The formula optimises for value-delivered-per-unit-time across the queue.
WSJF's theoretical basis is Don Reinertsen's queueing-theory work on product development flow. The practical translation: small high-value items always beat large items, and large items only justify themselves when their value-density (CoD/Size) exceeds the alternatives. Scoring is relative (Fibonacci or similar): pick the smallest item, give it a 1, score everything else relative to it. The common failure modes are (1) gaming the scores to justify pet projects, (2) ignoring WSJF when a HiPPO weighs in, and (3) re-scoring every item every meeting until the relative anchor is lost. A WSJF process that survives 6 months is usually disciplined enough to produce real benefit.
Related terms
- Cost of delay
Cost of delay is the economic impact of not having a feature available — revenue forgone, cost incurred, risk that compounds — expressed as a per-unit-time number (per week, per month).
- Portfolio kanban
A Portfolio Kanban is the visual board that tracks large initiatives (portfolio epics) across discovery, analysis, implementation, and done — with WIP limits at each state to constrain how much portfolio work is in flight.
- RICE scoring
RICE scoring is a prioritisation framework from Intercom that ranks initiatives by Reach (how many users affected), Impact (per-user effect, typically scored 0.