Effort Estimation

Produce honest, useful estimates without false precision. Estimates are forecasts, not commitments — always ranges, always improving as you learn more.

Workflow

Step 1: Ensure Tasks Are Defined

You can't estimate undefined work. Tasks must be broken down (use feature-planning if not), have acceptance criteria, and have at least a sketched technical approach. "I can't estimate this until we do a spike" is a valid and responsible answer.

Step 2: Choose the Method

T-shirt sizing for roadmap and early-stage sizing; story points (Fibonacci) for sprint planning and velocity tracking; three-point estimation for budget requests and high-uncertainty, high-stakes work; time-based only for well-understood tasks. See references/estimation-methods.md for detailed guidance on each method.

Step 3: Apply It

Estimate per task, not the project as a single unit; relative to known work rather than in absolute terms; as a team where possible (the familiarity gap between estimators reveals hidden complexity); with uncertainty explicit. Re-estimate when spikes complete or requirements clarify.

Step 4: Translate for Stakeholders

Convert to time or cost via team velocity or loaded cost, add a 20-30% buffer for unknowns, and communicate a range in stakeholder language — weeks and dollars, not story points. A single number becomes a commitment; a range communicates confidence.

Say when the number gets revisited. A range nobody revisits hardens into the commitment you avoided giving — so hand over the estimate with its re-forecast attached: the next point where real data replaces assumption (a phase boundary, the end of a spike, the first sprints of actuals), and what would move the number. That sentence is what keeps an early-discovery estimate honest; without it, "wide range" is just a number the stakeholder rounds down.

Step 5: Track and Calibrate

Compare estimated with actual — per sprint on delivery work, at each phase boundary on a project-sized estimate — look for systematic bias, and recalibrate on the last 3-5 data points, not the all-time average.

Principles Applied

• KISS: Use the simplest estimation method appropriate. T-shirt sizing is fine for most roadmap decisions.
• Honesty over optimism: A realistic estimate that disappoints a stakeholder is better than an optimistic estimate that misses a deadline.
• YAGNI: Don't estimate items far in the future with precision. Estimate near-term work in detail, far-term work in ranges.