Metrics — Learning Yield, Carry Cost, and More

Definitions, formulas, and pragmatic collection methods to make debt actionable.

Recommended metric set:

  • Learning Yield = insights or reduced uncertainty per unit cost/time.
  • Carry Cost = recurring friction time per period (e.g., hours/sprint).
  • Reversibility Score = effort to unwind a path (1–5 or hours).
  • Option Value Index = future flexibility estimate / investment.
  • Debt Velocity = creation vs transformation rate per period.
  • Risk Exposure = likelihood × impact, normalized by boundary.

Collection tips:

  • Embed small fields in ADRs and incident reviews; avoid separate tools.
  • Sample weekly; trends matter more than precision.
  • Visualize hotspots by system boundary and class (structural, cognitive, etc.).

Use thresholds (“red zones”) to trigger refinance sprints automatically.