I would be remiss if I did not include at least some discussion of brands in a conversation about product management.
For the uninitiated, a brand has been traditionally defined as a particular product that is manufactured by a particular company. McDonald's is a specific brand of fast food; Starbucks is a specific brand of coffee. In recent years, however, the concept of branding has been expanded to encompass any "particular identity or image regarded as an asset." By this definition, the term brand essentially serves as both (1) a definition of what makes your particular offering unique compared to other alternatives and (2) a substitute for a person's or organization's reputation -- and marketing folks have tried to find various ways to both highlight the uniquely special aspects of a particular brand as well as cultivate or build high-quality brands (i.e. strong positive reputations).
Why does this matter for a product manager? Your product's brand is a key asset in both acquiring & retaining customers as well being able to launch new products or offerings if you so choose. Being a respected brand indicates that customers have come to trust you to deliver product that is uniquely aligned with their interests and have confidence that your actions in the future will result in positive outcomes -- even if there may be negative short-term consequences. Trading some of your "brand equity" to buy time with customers or get customers to overlook short-term concerns is an option available only to those organizations with a strong brand.
Note that brands do not have to be external. Your department or function almost certainly has a brand within your organization. Understanding how you are perceived by others in the organization can often go a long way toward planning successful product releases.
The topic of brand management could fill an entire blog series on its own. If there's one key element that I have found critical to building and maintaining a strong positive brand, it is consistency. Customers have a lot to think about and often have many different tasks to accomplish. If they are comfortable that your product will deliver the same result in the same fashion each and every time, then they will trust your product to accomplish its particular task and consider it as "one less thing they have to worry about." In contrast, if they have an uneven or inconsistent experience, then they will not trust your product and instead feel that they must verify the results after each interaction. This adds to their mental workload instead of taking from it -- and will likely cause them to eventually give up on your product in favor of a more consistent competitor or substitute.
As with the other marketing topics covered so far, this only skims the surface of this material. At this point, it's enough to know that product managers should be aware that their product and their organization both have brands and that building strong brands for both can yield benefits beyond those delivered by the core product itself.