I actually had a prospective employer ask me this question. In all fairness, what is a given in larger companies with deeper pockets might not be understood (or seen as affordable) by smaller companies having to do more with less, requiring their teams to wear many hats.
With that said, here goes...
When it comes to a product development team, it's essential to understand the distinct roles and responsibilities of the Product Manager, Product Owner, and Project Manager. Each position plays a vital role in the successful execution of product development, but they each have unique skill sets and focus areas that differentiate them from one another.
First, let's discuss the Product Manager. They're responsible for defining the strategy and roadmap for the product. They work closely with stakeholders, customers, and the development team to gather requirements, prioritize features, and ensure that the product aligns with the overall business goals. The Product Manager also acts as the voice of the customer, ensuring that the product meets the needs and expectations of its target audience. In addition, they conduct market research, competitive analysis, and work with the marketing and sales teams to define product positioning and go-to-market strategies. The Product Manager is responsible for the whole Product.
Then there's the Product Owner who is responsible for representing the customer and stakeholder needs to the development team. They work closely with the Product Manager to prioritize features, create user stories, and define acceptance criteria. The Product Owner collaborates with the development team during the sprint planning, reviews the product increment, and provides feedback on the work completed. They are also responsible for making decisions and trade-offs during the development process to ensure the product meets the customer's needs and delivers value. The Product Owner may be one of several Product Owners, focused on parts of the overall Product. (sales flow, account management, lead generation, etc.)
Lastly, the Project Manager is responsible for overseeing the execution and delivery of the product. They manage the resources, timelines, and risks associated with the project, ensuring that the team stays on track and delivers the product within the specified budget and timeline. The Project Manager coordinates the efforts of cross-functional teams, communicates with stakeholders, and manages any changes or challenges that arise during the development process. (The Project Manager may be managing concurrent project delivery for different Products.)
So, the Product Manager focuses on defining the product strategy and roadmap (the Vision/the Why), the Product Owner represents the customer and stakeholder needs to the development team (the Program/the What), and the Project Manager oversees the execution and delivery of the product (the Implementation/the How).
While there may be some overlap in their responsibilities, each role brings a unique perspective and skill set to the product development process. By understanding the differences between these roles and ensuring clear communication and collaboration among them, product development teams can effectively deliver successful and impactful products to the market.