Why Estimations Are So Hard

Most project estimates sound great right up until delivery begins. Timelines shift. Scope stretches. What felt clear at the start suddenly becomes hard to pin down.

That’s why we approach things differently.

Estimation isn’t about setting a rigid deadline or making optimistic guesses. It’s a structured, evolving process built around real-world data, team experience, and open and honest communication. It's also embedded within our PRINCE2 aligned project management framework.

Why does it matter? Because estimation touches almost every part of a project:

It sets stakeholder expectations from day one.

It directly impacts budget approvals and resource planning.

It plays a huge role in team stress, especially if goals feel unreachable.

It influences trust. If estimates constantly miss the mark, confidence drops.

When estimations aren’t delivered, there’s a perception of budget blowouts and inevitable delivery delays.

A good estimation process doesn’t just inform a timeline; it shapes the success of the project and the relationships that support it.

Why We Use Time-Based Ranges

Instead of story points or t-shirt sizes, we estimate in actual time; hours, days, or weeks.

Time-based estimates are easier for clients and stakeholders to understand. They also ground conversations in real expectations rather than theoretical effort.

Because early-stage projects often come with uncertainty, we use ranges (e.g. 2–4 weeks) rather than fixed figures. That way, we allow space for discovery without letting the plan drift too much.

We also consider the human factor. People tend to be overly optimistic when predicting the future. Ranges help protect against that, giving us a more realistic, agreed upon window for delivery.

Hear directly from David Burkett, CGO and Director of WorkingMouse, as he breaks down how we approach estimation.

Estimation That Evolves with the Project

Every estimate is a starting point, not a promise set in stone.

As the project evolves, so does our understanding. A new risk may emerge, or a technical spike might reveal added complexity. In either case, we adapt the estimate based on what we’ve learned.

We embrace change with an agile mindset. Not just in how we work, but in how we track and communicate shifts to the plan. Estimation is most valuable when it remains an evolving part of the project conversation, not just a number in a spreadsheet.

We Estimate at the Milestone Level

Rather than estimating every single task, we estimate in milestones. The high-impact pieces of work that show progress.

Each milestone typically contains several streams:

Application logic

Admin and platform features

Project management and accessibility

Infrastructure and non-functional requirements

During planning, we estimate as a team, which includes solution architects, developers, BAs, and designers. We discuss the scope together and zero in on a range we’re all comfortable with.

We might start broad: “Could we do this in two weeks?”
If that’s too tight, we try: “How about two months?”
Then we narrow it down until we land on a shared, realistic timeframe.

This approach doesn’t just give us structure; it keeps the whole team aligned on what's achievable.

Estimation Backed by Data

We don’t pull estimates out of thin air. Every estimate is informed by data from past projects. This includes what worked, what didn’t, and what patterns tend to repeat.

We combine those lessons with the team’s insight to build a clearer picture of what feels realistic. It’s not about being perfect, it’s about setting realistic expectations from the start.

As we deliver, we check how things are tracking. If something shifts, we don’t ignore it. We adjust and keep learning.

Our Tools Make Estimation Smarter

We use technology to keep things smooth, visible, and consistent:

Model-Driven Engineering (MDE) lets us map requirements visually and build reusable components.

DevOps pipelines automate code checks, run tests, and surface issues early.

These tools don’t just speed things up, they help keep everyone on the same page while improving the quality of our estimates.

How We Manage Estimation Risk

Estimation risk is real, and we treat it seriously.

In line with our PRINCE2 approach, estimation is identified early as a project risk and assessed for likelihood and impact. Often scoring high due to its influence on budget, scope, and delivery outcomes.

To reduce that risk, we take proactive steps:

Discovery – to clarify scope and reduce ambiguity

Modelling – to ensure shared understanding of every requirement

Technical Spikes – to timebox the exploration of high-risk or unknown areas

Strict Scope Control – to prevent assumptions and ensure estimates are grounded in agreed definitions

These strategies are part of our ongoing effort to keep estimation risk manageable and continuously improving.

A Good Estimate Builds Confidence

When estimation works, it does more than create a schedule, it also creates trust.

It helps stakeholders plan with confidence. It gives teams clarity and focus. And it supports smoother delivery with fewer surprises and far less guesswork.

Getting it wrong can cause things to spiral, leading to stress, missed deadlines, and a loss of trust. But getting it right (or at least honest and adaptive) builds credibility with everyone involved.

Key Takeaways

Know the purpose – Are your estimates part of a contract or just for planning? That distinction matters.

Confidence over precision – It's not about predicting the future to the minute. It's about building shared confidence.

Communicate constantly – Estimates are important, but updates to those estimates are even more critical.

Need a Second Opinion?

If your current estimation process feels more like guesswork than guidance, we can help. Whether you need a fresh pair of eyes or a framework to follow we’re happy to share what works.

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