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Planning and Estimation (PLA)

A date is a promise made to others; an estimate is a judgment under uncertainty. The greatest damage is not a wrong estimate (they all are, to some extent), but a wrong estimate…

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Level: 🟢→🔴 · Code: PLA · Matrix: PI

Why this topic#

A date is a promise made to others; an estimate is a judgment under uncertainty. The greatest damage is not a wrong estimate (they all are, to some extent), but an estimate that is wrong and presented as certain: it triggers cascading commitments (user training, customer communication, resource freezes) that collapse together. A mature schedule does not predict perfectly; it states how reliably it predicts, and readjusts without drama.

What this topic measures#

  • Axis: from imposed date to calibrated probabilistic forecasting.
  • Key indicator: forecast reliability (share of commitments met on date, average gap between estimate and actual).
  • Unit: % of commitments met; relative workload gap (± %); width of the announced range.

The five levels#

Level Short name Promise Typical indicator (orders of magnitude)
1 Imposed date We know when we are asked to deliver; we discover along the way whether it is feasible. Commitments met: < 30 to 40%
2 Milestone plan A plan with milestones and owners exists; deviations are visible when they occur. Commitments met: 40 to 60%
3 Shared estimation The team estimates itself, with explicit margin and assumptions; the announced date is a range. Met: 60 to 75%; workload gap ± 30%
4 Measured forecasting Forecast reliability is measured on historical data and used to announce dates. Met: 75 to 90%; workload gap ± 15 to 20%
5 Probabilistic forecasting Dates are announced with a confidence level (“85% before the 15th”); the plan adjusts without surprises with each new piece of information. Calibration: announced 85% ≈ observed 80–90%

Milestones by level#

ID Milestone Verifiable evidence
PI-PLA-1.1 A target deadline exists for each project. Date present in the project sheet.
PI-PLA-1.2 Main tasks are listed. List of work packages/deliverables.
PI-PLA-1.3 Delay is identified (even late) and stated. A past delay appears in meeting notes.
PI-PLA-2.1 Plan with milestones, main dependencies, and owners. Up-to-date planning diagram or table.
PI-PLA-2.2 The plan is updated at least at each milestone. Plan version history.
PI-PLA-2.3 Known vacations and unavailability are integrated. Plan cross-checked with the team calendar.
PI-PLA-3.1 Estimates are made by those doing the work (poker, Delphi, decomposition). Estimation workshop notes.
PI-PLA-3.2 Each estimate includes its assumptions and a range or margin. “Assumptions” and “min/max” fields completed.
PI-PLA-3.3 External dependencies (other team, data, vendor) are planned with margin. Dependencies listed with needed-by date and contact.
PI-PLA-3.4 Actual capacity (excluding meetings, support, incidents) is used, not theoretical time. Availability factor documented (for example 60 to 70%).
PI-PLA-4.1 Estimated/actual gap is measured for each completed item. Estimated/actual history over ≥ 20 items.
PI-PLA-4.2 A throughput indicator (velocity, cycle time) feeds forecasts. Throughput curve, cycle time (percentiles).
PI-PLA-4.3 Announced dates are based on history, with a calculated range. Dates with explained interval.
PI-PLA-4.4 Rebaselines are counted and analyzed. Number of replans tracked per project.
PI-PLA-5.1 Probabilistic forecasts (Monte Carlo simulation on history or equivalent) are used. Report with percentiles (50/85/95%).
PI-PLA-5.2 Calibration is verified: announced 85% hits about 85 times out of 100. Calibration table over ≥ 20 forecasts.
PI-PLA-5.3 Decision-makers reason with ranges and not a single date. Meeting notes citing ranges.
PI-PLA-5.4 Each new piece of information (incident, departure) updates the forecast in under 2 days. Update date vs event date.

Detailed reading by level#

Level 1. Signs: the date comes from the sponsor or an external event; the team compensates with late nights. Benefit: alignment on a real deadline. Does not guarantee: feasibility or quality. Difficulty: 1/5. Effort: 1/5.

Level 2. Signs: milestone plan, updates before reviews. Benefit: shared view of the sequence. Does not guarantee: that the plan holds against unexpected events; estimation remains a wish. Difficulty: 2/5. Effort: 2/5.

Level 3. Signs: the team explains its estimates; the range is accepted as normal. Benefit: more honest commitments; less end-of-project stress. Does not guarantee accuracy. Difficulty: 3/5. Effort: 2/5.

Level 4. Signs: you know your error rate; you say “based on our history, 80% chance before end of March.” Benefit: credibility with sponsors. Does not guarantee stability if context changes (new tech, refreshed team). Difficulty: 4/5. Effort: 3/5.

Level 5. Signs: forecasts recalculated automatically, calibration verified, decisions based on percentiles. Benefit: informed portfolio decisions. Does not guarantee absence of black swans. Difficulty: 5/5. Effort: 4/5.

Partial achievement and rating#

Common rule: see README.

  • 0.5: estimate made by the team but without written assumptions; history exists but is not used.
  • 1: evidence can be reviewed without oral explanation.
  • A partial 5: forecasts based on actual throughput (4.x acquired), simulation on one or two projects, calibration not yet measured (5.2 = 0). Score: about 4.2.
🧪 Example

Datamart team, kit delivery every two months. History: 12 kits, median cycle time 18 days, 85th percentile 31 days. Announcement: “the fix will be delivered in the December kit, with 85% confidence before the 20th.” The department manager knows what to tell their teams.

⚠️ Pitfall

Estimate turned into commitment. Symptom: the team systematically pads estimates. Cause: the estimate was used as a contract, and overrun was penalized. Remedy: separate estimate (judgment), target (wish), and commitment (decision), and write them separately.

⚠️ Pitfall

Goodhart: if velocity is a target, it inflates (point inflation). Velocity is for team forecasting, never for comparing teams.

💡 Expert tip

Estimates in person-days are biased by optimism (planning fallacy); the proven countermeasure is to estimate by analogy on comparable completed items (reference class forecasting) rather than by decomposition alone.

Move to the next level#

Possible means (optional)

  • 1 → 2: a milestone plan in a shared tool; see planning tools.
  • 2 → 3: collective estimation (poker, three-point), assumptions log; see Scrum in Practice and predictive methods.
  • 3 → 4: collect estimated/actual, cycle time, percentiles; see metrics and reporting.
  • 4 → 5: Monte Carlo simulation on history, calibration table, automatic recalculation.
🤖 AI

AI can suggest a breakdown, flag forgotten tasks, and compare with similar items; it does not have access to your team's real context and its estimates are often too confident: treat it as one more opinion to calibrate against history. See AI for Project Management (General, Then Data).

See also#

✻ Written by Claude Sonnet 5.5