In literature, it's often the outsider's perspective that offers the most honest and thoughtful analysis of a social environment.

Because his work is typically fairly critical of the values and social norms of the culture he writes about, this style of protagonist gives Fitzgerald an easy channel through which he can explore this criticism. His characters are generally immersed enough in a lifestyle to show it with the intimate knowledge of a participant, but also removed enough to demonstrate its flaws and shortcomings with candor and honesty.

Fitzgerald's role as a writer was also naturally conducive to embracing an outsider's perspective. To be a writer, especially one writing about communities and societies that are known to you, you have to operate at some degree of a remove by nature—your job is to observe and critique the world around you, and you're always balancing your need for objective perception with your desire to participate. To whatever extent you're operating in society, you're also researching it.

It's also worth considering that the decision to foreground an outsider is often considered safe and relatable because most people, at some point in their lives, have felt like one. Stepping into the surrogate role of the outsider protagonist feels familiar and comfortable as a reader, even in an unfamiliar setting.

An axiom of fiction writing is "write what you know," and Fitzgerald's outsider heroes or narrators reflect the author's own social location. Although he made it into the prestigious Princeton University, Fitzgerald's Minnesota roots were neither wealthy nor particularly well connected, and he engaged in self-destructive behaviors, such as flunking out of Princeton when he seemed en route to a successful career there. He also felt potentially inadequate and peripheral when Zelda's parents would not approve his marrying their daughter until he made a success of himself. Although he did, writing the best-selling This Side of Paradise and becoming the center of a bohemian 1920s world in France, he maintained the feelings of a person on the periphery.

This is probably best expressed in the characters Nick Carraway and Jay Gatsby in The Great Gatsby. Nick, like Fitzgerald, is the contemplative voyeur, watching and recording the dramas of other people's lives. Nick feels both peripheral to the charmed circle of vast wealth in which Tom and Daisy live, and peripheral to the grand drama of Gatsby's love of Daisy. Nick, the would-be stocks and bonds broker, wanders the streets of New York City in lonely exile, gazing in at other lives. This both alienates him and yet supremely positions him to be a commentator on his world.

Gatsby reflects the outsider, Fitzgerald, wanting to be let in—into the life of the young woman who is out of reach, into the world of wealth and education that Nick floats so easily through.

Fitzgerald was able to marshal his sense of being an outsider into a series of brilliant novels, catching a zeitgeist many of his generation felt and many today still do.

As with any opinion-based question, you will need to find support for your claim. Examples of evidence include citing passages from Fitzgerald's writing, considering the historical context in which he was writing, and examining Fitgerald's personal life for facts that might explain his writing.

Let's consider some questions that might help you decide on your claim/answer. What effect does Fitzgerald achieve by writing about this? How would his writing be different if he focused on a different kind of hero?

Personally, I think Fitzgerald wrote about people "on the edge of the glamorous life" because that was more realistic to his readers. The idea of the American Dream had an influence on many twentieth-century works. Most people dreamed of a better life, or a more glamorous life. I relate more to a character like Gatsby, who is on the edge of luxury, than I do to a character like Tom, who was born into it and doesn't know what it means to struggle financially. The eNotes study guide on Fitzgerald shows us how readers might identify with this as well:

If great art is born of great misery, that might help explain Gatsby's success. The novel tells the story of Fitzgerald's "Lost Generation" during the Jazz Age. The term "Lost Generation" describes the young people of the 1920s who, like Fitzgerald, felt purposeless in a world of excess.

We can also explain Fitzgerald's choice in favoring characters on the edge of glamour by looking at his personal life. His wife, Zelda, was from a higher social class. In that sense, Fitzgerald was on the edge of that higher life, and perhaps that is why he chose to write characters who also felt like that.