Building Confidence Through Better Project Estimation

Confidence is one of the most frequently cited traits of effective leaders. Whether you look at Inc., Forbes, or any other list of leadership qualities, confidence is always near the top. For project leaders, confidence is about conviction in the plan. Teams, sponsors, and stakeholders take their cues from the project manager. If you stay calm and confident, they are reassured and more likely to rise to meet challenges positively.

But confidence, like trust, must be earned through credible estimation, which helps stakeholders and the team buy into a realistic plan and feel assured in its feasibility.

Why Confidence Matters in Projects

Confidence is contagious. When the project manager demonstrates confidence, the team’s confidence will improve. Stakeholders are reassured, sponsors are more willing to provide needed support, and the project environment becomes more resilient to setbacks.

Earnestness is not about unquestioning optimism. It’s about demonstrating that the plan is realistic and the project achievable. This is why estimation and planning sit at the very heart of confidence-building. In my own practice, I’ve seen how plans with explainable assumptions and transparent, accurate estimates can transform stakeholder skepticism into genuine buy-in.

The Estimation Challenge

The PMBOK® Guide Sixth Edition acknowledges the difficulty of estimation. In the initiation phase, projects may rely on a rough order of magnitude (ROM) estimate ranging from -25% to +75%. Later, as more information becomes available, definitive estimates can narrow to -5% to +10%.

That leaves project managers with a formidable gap to close. Moving from a 75% margin of error to 10% requires discipline, process, and, often, organizational support. Many organizations strive for tighter ranges upfront because it helps with portfolio management. In my experience, the best organizations either have formal policies or, at a minimum, an unstated expectation that estimates will be more precise early on.

This challenge inspired me to invent an estimation approach specific to Siebel software implementation projects (but generalizable to all pre-built software implementations) that produces initiation estimates with explainable units and documented assumptions. Users could present stakeholders with a plan that wasn’t just a guess, but a credible roadmap. The ability to show how numbers were derived gave sponsors confidence and helped portfolio managers make better decisions.

Effort vs. Duration Estimating

One of the most common pitfalls in estimation is consistently using duration-based thinking. Team members often worry about what might happen, add excessive padding, or forget critical steps, leading to inaccurate estimates.

I’ve found it far more effective to coach team members to think in terms of effort. Asking, “What would it take to complete the task if you could do so uninterrupted?” helps team members feel more in control and less anxious about deadlines.

My estimation method leaned heavily on this principle. By focusing on effort, I could strip away the anxieties of “when will I take my vacation” and “how will I allocate my time to multiple projects,” and instead anchor estimates in the actual work required. Combined with scheduling tools, this approach produced durations that were both realistic and defensible.

I also apply a rule of thumb: never schedule a resource at more than 80–85% utilization. This accounts for vacation, training, sick time, and professional courtesy (helping colleagues). It also reduces the burden of asking team members to plan their time off months in advance. It also allows for adjustment for those working on multiple projects. These simple adjustments make schedules more realistic and reduce stress across the team.

Framework for Effective Estimation

Estimation should never be a guess or based on blatant padding; a structured framework ensures consistency and credibility. Key elements include:

• Business clarity: Ensure the problem is well articulated and understood.
• Deliverable focus: Stakeholders must understand what is being produced.
• Risk and assumptions log: Document early and revisit often.
• Dependencies mapping: Be sure to identify external factors that could impact the project.

When I applied my estimation invention, these elements were built into the process. Every estimate was tied to a documented assumption, every dependency was visible, and risks were logged from the start. This transparency made it easier to defend estimates and gave stakeholders confidence that the plan was grounded in reality.

Critical Success Factors (CSFs) of Estimation

Beyond process, several success factors elevate estimation quality:

• SME (Subject Matter Expert) input: Engage subject matter experts with deep industry knowledge.
• Historical data: Use past project metrics whenever possible.
• Multi-point estimates: PERT (Program Evaluation and Review Technique) estimation incorporates optimistic, pessimistic, and most-likely values and can be used to calculate confidence ranges and answer “what if” questions.
• Validation: Apply both top-down and bottom-up techniques; compare the results.
• Stakeholder buy-in: Confidence increases when stakeholders see their inputs respected and reflected.
• Resource alignment: Assign the best people to each task.
• Schedule compression: Explore fast-tracking, crashing, or other techniques before changing effort.
• Worker involvement: Include the person doing the work in any effort-change discussion.

My own approach considered all of these factors. For example, I often performed estimates twice (once top-down, once bottom-up) and compared the results. During the estimation process, I reviewed available historical data. When estimates were complete, I sought SME input. If discrepancies arose between top-down and bottom-up estimates, I used them as teaching moments with the team, showing how assumptions shaped outcomes. Finally, I assigned the best resource and always consulted them if the level of effort had to change. This improved accuracy and built trust.

Managing Expectations and Team Dynamics

Estimation is as much about behavior as it is about numbers. Managing expectations around savings and overruns is critical.

In my projects, I often told team members that any “savings” on non-critical path tasks were theirs. They could use this time for professional development, pet projects, or providing professional courtesy in helping others. This created a positive incentive structure.

On the other hand, overruns on the critical path were unacceptable. Team members were expected to put in the time necessary (within reason) to bring tasks back on track. These overruns and how they were handled became valuable lessons learned for future projects.

My approach balanced accountability with empowerment. It reinforced the importance of the critical path while rewarding efficiency elsewhere. And because estimates were rooted in explainable assumptions, it was easier to have honest conversations about where things went wrong and how to improve.

Confidence is Essential

Confidence is essential for project leadership, but it must be earned through credible planning and estimation. By shifting from duration to effort-based estimating, applying structured frameworks, leveraging critical success factors, and managing expectations, project managers can build plans that inspire confidence.

My own estimation journey taught me that having an estimation process can close the gap between rough and definitive estimates. The estimation process created a culture of confidence and accountability.

In the end, showing confidence in the plan is not about optimism alone. It’s about transparency, process, and shared ownership. With better estimates, project managers can lead with confidence and deliver projects that meet the triple constraints.

Now available in our downloads (Miscellaneous Files and Templates): A Project Estimation Confidence Scorecard Template to ensure that estimation best practices are followed and that confidence in estimates is high. Free sign-up for our downloads is at https://accidentalpm.online/downloads. Contact us at [email protected] if you need assistance.