Part of what makes Fitzgerald's novel such a favorite piece is the way he is able to analyze the society of which he was also a part. Through his characters, he not only captures a snapshot of middle- and upper-class American life in the 1920s, but also conveys a series of criticisms as well.
What's so great about Gatsby?
Through the characterizations in The Great Gatsby, Fitzgerald explores the human condition as it is reflected in a world characterized by social upheaval and uncertainty, a world with a direct underlying historical basis. By emphasizing social groupings and how they do or do not interact with each other, Fitzgerald establishes a sense of urgency.
The Jazz Age society so clearly shown in The Great Gatsby is, in effect, on a very dangerous course when people like Tom, Daisy, and Jordan are at the top of the ladder, working hard to ensure no one else can climb as high as they. Through Gatsby, Fitzgerald demonstrates the enterprising Jazz Ager, someone who has worked hard and profited from listening and responding to the demands of the society.
Unfortunately, despite his success, Gatsby (and all of the people he represents) is never able to capture his elusive dreams. Fitzgerald's story, although a fiction, is informed by reality, helping to make it one of the most treasured pieces of early 20th century American fiction.