There is no story without a struggler.
In Ancient Greek, protagonist referred to the "one who plays the first part, the chief actor." But its root, agonist, illuminates the key function of this character.
Agon is the ancient Greek term for conflict, struggle, or contest. The agonist is, thus, one who struggles. But in most stories, there are at least two.
There is a protagonist who usually struggles for something, and an antagonist who struggles against. Yin and yang, darkness versus light, good against evil. The conflict is at the core (and, as we'll see later, the conflict is the story.)
Protagonists are usually heroes, but they don't have to be. Michael Corleone, Patrick Bateman, Amy Dunne, Sweeney Todd, are all excellent examples of villainous protagonists. Some would say they have to be likable, or at least, understandable. What matters is they are all at the center of the story because something happens to them. They have a problem to solve, a mountain to climb, an enemy to overcome.
In practical applications of storytelling, such as community organizing or business, a common mistake is to believe that the story you present is about you, your product, your mission.
The issue is, as Nancy Duarte reminds us, that "audiences react very badly to arrogance and ego." Unless we go in for a lecture, we don't like to be preached to, especially when it's done in a patronizing tone.
When you're building an audience, remember you are not the hero.
They are the agonists. Tell the story from their perspective.