As a product manager, I am constantly trying to explain what exactly a product manager does (sometimes I feel like saying a PM's job responsibility is explaining what exactly they do). But the main job of a PM, the sine qua non of their job responsibilities is to understand, and speak on behalf of, the customer.
The customer isn't in the room to tell your team what problem they need to solve. And even if they were there, the customer probably wouldn't have the right words. From Clay Christensen's Competing Against Luck:
Identifying and understanding the Job to Be Done is key, but it’s just the beginning. After you’ve uncovered and understood the job, you need to translate those insights into a blueprint to guide the development of products and services that customers will love. This involves creating the right set of experiences that accompany your product or service in solving the job (as we’ll discuss more fully in chapter 6). And finally you have to ensure that you have integrated your company’s internal capabilities and processes to nail the job consistently (chapter 7). Creating the right experiences and then integrating around them to solve a job, is critical for competitive advantage. That’s because while it may be easy for competitors to copy products, it’s difficult for them to copy experiences that are well integrated into your company’s processes.
If you're unfamiliar with jobs to be done, here's a great summary.
In two sentences, Clay Christensen developed the jobs to be done framework to help put the customer's voice back in the room where products are being developed. A customer has a job, they need something to do that job, it's up to the product to be the best fit to get "hired" to do the job.
And it's on the product manager to understand that job that needs to get done and advocate for the customer in the room. And I mean that literally.
The word "advocate" traces its roots to the Latin word "advocare" meaning "to summon, call to one's aid."
The noun form of the word "advocate" is a synonym for "lawyer."
Lawyers get a bad rap, but they are their client's champions. They understand what their clients need, speak the language of the court, and speak in the room on their behalf.
That is exactly what product managers have to do for their customers.
It can be very easy to bogged down with details when working on a product or feature. Things like metrics, acronyms, and process tend to take up our focus. But if a product person loses track of the customer's voice, it's likely that no one else will pick it up.
Every team is full of motivations and perspectives that act like crosswinds, pushing the product in different directions. Sales people are focused on closing, designers are focused on clarity and unifying interactions, developers are focused on stability and speed. Even the company itself blows in a certain direction. As David S. Duncan points out in The Secret Lives of Customers:
Like Ptolemy, companies try to explain the world by putting themselves—or their products—at the center of their models of how things work. But to understand what’s really going on, you have to focus on what’s really driving things: customers and their jobs to be done.
Jobs to be done is one of many frameworks that can be used, but whatever a product manager prefers, it is their primary responsibility. Just as it's primarily on the lawyer (not the judge, bailiff, jury, or witnesses) to advocate for the client in the courtroom, it's on the product manager to advocate for the customer on a project.