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Team Planning Fibonacci

By Ishy Bansal

Does Size Matter? The Role of Modified Fibonacci in Team Planning

Throughout my career, working with various agile teams, one of the recurring challenges I’ve encountered is task estimation. Teams often grapple with the question: Does size matter? In my experience, the answer is a nuanced yes.

The Modified Fibonacci Sequence: A Tool for Clarity

Let me share a story. Early in my career, I worked with a team struggling to estimate tasks. Meetings dragged on as we debated the difference between “4 days” and “5 days” That’s when I introduced the modified Fibonacci sequence (1, 2, 3, 5, 8, 13, and so on). Why Fibonacci? Because as tasks grow larger, their complexity and uncertainty increase disproportionately. The structured jumps in this sequence cut down on endless debates and helped us focus on the broader picture. For example, it was easier for us to agree that a task was a “5” rather than splitting hairs over minor differences.

How Size Affects Planning

In another team, I discovered the power of understanding task size to balance workloads and anticipate challenges. However, I’ve learned to emphasise that size is only a guideline, not an absolute truth. A task estimated as “5” points may take slightly more or less time depending on unforeseen variables—and that’s okay. The modified Fibonacci system nudged us toward relative, not exact, estimates. It allowed us to stay flexible and focus on delivering value rather than striving for unattainable precision.

The Pitfall of Overestimating Estimation

One of the most valuable lessons I’ve learned is how too much focus on estimation can harm the planning process. I’ll never forget a particular sprint planning session where the team spent over an hour debating whether a task was a “5” or an “8.” The discussion drained energy and momentum. From that day, I implemented a simple rule of thumb: if we’re debating for more than a few minutes, it’s time to pick a number and move forward. It’s better to err slightly and adjust later than to waste the timebox.

Effective estimation sessions should:

  • Be time-boxed to prevent over-analysis.

  • Focus on relative size rather than absolute accuracy.

  • Encourage collaboration, ensuring all team members’ perspectives are heard.

Planning vs. Estimation

One mistake I’ve seen teams make (myself included!) is conflating estimation with planning. Estimation is about gauging effort and complexity; planning is about sequencing tasks, allocating resources, and identifying dependencies. Overemphasis on estimation can leave less time for these critical activities.

Instead of aiming for perfect estimates, I encourage teams to aim for usefulness. The goal is to provide just enough information to make informed decisions. This balance allows teams to stay agile and adaptable.

Additional Tips for Effective Team Planning

Here are some practices I’ve found valuable over the years:

  • Prioritise Collaboration: Engaging the entire team in estimation and planning surfaces diverse insights and promotes shared understanding. Some of my most productive planning sessions happened when everyone—from developers to testers—shared their perspectives.

  • Use Historical Data: When working with a seasoned team, I’ve found it helpful to leverage past experiences to inform new estimates. Patterns often emerge that make estimation faster and more accurate.

  • Review and Adjust: In one memorable project, we revisited our estimates mid-sprint to ensure they still aligned with reality. Treating estimates as living guidelines rather than rigid commitments saved us from misalignment.

  • Simplify Where Possible: When a task feels too big to estimate confidently, break it down. I recall a time when splitting an overwhelming “13”-point task into smaller pieces made it far more manageable and boosted the team’s confidence.

Conclusion: Focus on Value, Not Numbers

Reflecting on these experiences, I’ve learned that while the size of a task matters, it’s the value it delivers that counts most. The modified Fibonacci sequence is a helpful tool to simplify complexity and guide discussions, but it’s only one piece of the puzzle. Teams thrive when they balance thoughtful estimation with actionable planning. By spending less time debating numbers and more time delivering value, I’ve seen firsthand how teams achieve real results where it matters most—in their outcomes.