Agile teams live or die by sprint velocity. But if your numbers jump wildly between sprints, it’s not just annoying — it’s a sign your process is broken.
Let’s break down why velocity gets inconsistent, and how to fix it before it wrecks your planning.
1. Vague or Rushed Estimations
If your team spends 30 seconds per task and just picks a number, don't expect accurate sprints. Without proper discussions and consensus, story points are often just guesses.
✅ Fix: Use Planning Poker to force thought and conversation. Anonymous voting and structured rounds reveal misunderstandings before the sprint starts.
2. Scope Creep Mid-Sprint
Do stories change halfway through? Are bugs or extra work being bundled in silently?
✅ Fix: Set strict DoD (Definition of Done) rules and estimate bugs separately. If bugs take significant time, estimate them like any other task.
3. Team Composition Keeps Changing
Did someone go on vacation? New devs join mid-sprint? If your team’s capacity changes every week, so will your velocity.
✅ Fix: Track team availability and adjust expected velocity accordingly — don’t just reuse old numbers blindly.
4. Inconsistent Story Sizing
If a “5-pointer” sometimes takes half a day, and sometimes takes 3 days — your scale is broken.
✅ Fix: Establish internal examples for each point level (e.g., “This story is a 3, because it’s like our login modal task from Sprint 12”).
5. No Historical Review
If you never revisit past sprints, you can’t improve future ones.
✅ Fix: During retro, check how accurate estimates were. If the team constantly underestimates 8-pointers, rethink how you handle them.
Final Word
Unstable velocity usually means unstable planning. And that’s often caused by poor estimation habits. Switch to structured, consistent methods like Planning Poker and start getting predictable again — without sacrificing speed.