Impact of new team members on velocity
We just added 2 new developers to increase delivery capacity. Should we expect velocity to increase immediately, or will it drop first while they ramp up? Management expects more output starting next sprint.
Short answer: Velocity will DROP 20-30% for 2-3 sprints before recovering.
Why Velocity Drops:
- Existing team members spend time mentoring/onboarding
- Code reviews take 2x longer (explaining context)
- Pair programming reduces individual output temporarily
- New members ask questions, breaking flow
- Onboarding tasks don't produce features
Typical Timeline:
- Sprint 1-2: Velocity drops 20-30% (onboarding overhead)
- Sprint 3-4: Returns to baseline (new members contributing)
- Sprint 5+: Exceeds previous velocity (team is larger AND efficient)
What to Tell Management:
"Adding 2 developers is an investment. We'll see temporary 20% velocity drop for 2 sprints while onboarding, then 40% velocity increase by sprint 5."
We saw exactly this. Added 3 people, velocity dropped from 45 to 32 for two sprints. Managers panicked. By sprint 4 we were at 60 points. Patience is key.
This helps me set expectations with leadership. The 2-3 sprint timeline is perfect for planning communications. Thanks!
Pro tip: Track "effective team size" separately from headcount. 2 new developers = 0.3 effective contributors for first month, 0.7 by month 2, 1.0 by month 3.