Product vs. Project Manager Business Cases: What You’re Missing

The Core Difference Between Product and Project Business Cases

A product manager’s business case is a comprehensive set of calculations focused on making or saving money in the short or long term from a business idea. This financial projection answers key questions like, “How much financial benefit can we achieve from this?” Typically spanning three or more years, it takes time to generate returns from a business and is essential for securing investment approvals. It also sets performance targets for tracking post-launch progress.

A project manager’s business case, on the other hand, is a project document designed for the duration of a project or initiative. Projects are usually kicked off after a decision has been made to start working on something, with a defined deadline. For product launches, the project’s duration aligns with the product’s launch date and ends once the product becomes operational. In this context, the project manager’s business case focuses on covering the costs of running the project—not the product—and includes resources like development, design, and testing. It may also reference financial benefit projections from the product manager’s business case.

While less calculation-intensive, the project manager’s business case delves into other aspects, such as risk analysis, and serves as a governance tool for resource allocation.

But What Does That Mean in Real Life?

When I started in product management back in 2008, I attended a business case training that was project management-focused. At the time, I didn’t know business cases were also created by project managers.

It was a two-day course, and I was impressed by the attention to detail in terms of documentation, stakeholder management, risk analysis, basic cost-benefit analysis, and intangible benefits. However, by the second day, it became clear that we weren’t going to dive deeply into comprehensive calculations and financial modeling—the very core of what my job required. While the training was valuable for learning about documentation, it didn’t prepare me for the demands of product management business cases.

As I gained experience at companies like Ericsson, Deutsche Telekom, Vodafone, and Telefónica O2, I realised that product managers’ business cases are fundamentally different. They require detailed, comprehensive spreadsheets with dozens of tabs for financial modeling, prices, revenues, OPEX and CAPEX calculations, ARPU, churn rates, and key metrics like cash flow, payback periods, and NPV. Creating these business cases often involves working closely with business finance, technology finance, sales teams, vendors, and project and program managers.

Unified Communications Platform Example

The Scenario:
In this role, my business case was the official document used to secure investment approvals during governance meetings. At each decision gate, I updated the business case, sat down with Finance to ensure alignment, and worked with local markets to validate revenue and cost calculations. This business case also served as the benchmark for tracking financial performance post-launch.

Group and Local Dynamics:
In large organisations, there is often a group entity responsible for overarching investments and local entities focused on market-specific execution. This structure creates distinctions like:

• Group CAPEX: Covering resources like global development teams and shared software licenses.
• Local CAPEX: Addressing market-specific costs, such as integrating the platform into regional systems.

As the group product manager, my business case reflected this complexity, ensuring that both group and local revenues and costs were accurately represented. I collaborated with Group Finance, local finance teams, and technology finance to align on vendor costs and other key metrics.

Once the investments were approved using my business case, a project manager was assigned to kick off the development. While the project manager created their own business case for internal governance, they referenced my business case for CAPEX investments, OPEX calculations, and revenue projections. This reinforced the product manager’s business case as the official financial document driving investment decisions.

How Commsbrief Fills the Gap

At Commsbrief, we recognise these nuances and offer tailored training to help professionals master the art of creating impactful business cases.

In my Business Case Masterclass and Executive Courses, we go beyond theory to:

• Build comprehensive financial models.
• Calculate critical metrics like NPV and payback periods.
• Align cross-functional teams for successful execution.

This training is built on years of experience creating, owning, and defending product management business cases in real-world scenarios. You’ll learn how to address tough questions from Finance, secure CAPEX approvals with confidence, and manage vendor relationships effectively—all using real examples from my career.