A product manager asks when a large project will be done. How do you answer?

Summary

With a range and a confidence level based on the team's actual throughput — for example '50% likely in 12 weeks, 85% in 14' — and a commitment to re-forecast weekly as scope and progress change.

Longer Answer

Summing estimates gives an optimistic single date because it ignores variation, interruptions and newly discovered work. A Monte Carlo simulation over the team's weekly throughput history produces a distribution of finish dates. If a single external date is needed, use a high-confidence percentile and say it's a commitment level. Reduce uncertainty over time by slicing work smaller and limiting work in progress.

Key Points

• Ranges with confidence, not single dates
• Forecast from throughput history (Monte Carlo)
• Re-forecast weekly

Deep dive: Forecasting Delivery Honestly

What interviewers look for

Honest, data-based forecasting and stakeholder communication.

Red flags

• A single date from summed estimates
• Padding estimates to protect the team