Malcolm Gladwell's Outliers: The Story of Success features many examples of cultural legacy from around the world. There's the section on Jewish lawyers in mid-twentieth-century New York, whose legacy of being poor and oppressed ended up a boon to their success. There's the chapter on Canadian youth hockey players and the importance of being born within a specific set of months. Then there's the epilogue, containing the author's own family backstory that led to his personal success. Throughout these various stories, Gladwell showcases how cultural legacy contributes to both positive and negative aspects of life.

In the introduction, Gladwell discusses "The Roseto Mystery," where a physician named Stewart Wolf discovered that Rosetans were far less likely to have medical issues related to heart disease:

In transplanting the paesani culture of southern Italy to the hills of eastern Pennsylvania, the Rosetans had created a powerful, protective social structure capable of insulating them from the pressures of the modern world. The Rosetans were healthy because of where they were from, because of the world they had created for themselves in their tiny little town in the hills.

In this section of the book, Gladwell shows how "the paesani culture" of social interaction, in addition to their isolation from neighboring towns, helped to protect them from heart disease. Their commitment to their Italian legacy—hard work, healthy eating, social interaction, etc.—is indeed a "mixed bag" of both strengths and weaknesses. In addition to the lack of heart disease, there was "no suicide, no alcoholism, no drug addiction, and very little crime." Additionally, by isolating themselves from nearby towns that consisted of other cultures, they were able to hold onto their Italian culture. There are, however, a few negatives that come with their approach to their heritage; in straying from the healthy lifestyle that was prevalent in Italy, they ate fatty foods, smoked heavily, and struggled with obesity: "a whopping 41 percent of their calories came from fat." One gets the sense that these negative aspects of life in Roseto could have been avoided had they clung tighter to their Italian legacy; however, they are far outweighed by the positive aspects listed above.

One example of how cultural legacy can be negative comes in chapter six. Gladwell tells the story of two feuding families, the Howards and the Turners, and how their cultural legacy contributed to the conflict:

"Stop that!" Will Turner's mother snapped at him when he staggered home, howling in pain after being shot in the courthouse gun battle with the Howards. "Die like a man, like your brother did!" She belonged to a world so well acquainted with fatal gunshots that she had certain expectations about how they ought to be endured. Will shut his mouth, and he died.

Here, the cultural legacy is that of "fatal gunshot"-based quarrels and the two families's indifference to the continuing violence. Mrs. Turner's retort to her son "howling in pain" says it all; she had grown so accustomed to the feud's death toll that she criticized him for holding onto his life. This was not limited to these two members of the Turner family; countless Howard and Turner family members perished because of the conflict, as well as a few innocent bystanders. This example of violence-begets-violence is clearly a negative example of how cultural legacy can influence a society.

Gladwell argues that each culture brings with it strengths and weaknesses. This mixed bag of "cultural legacies" affects the individuals within that culture. For example, in chapter 7, the author analyzes the Korean airline crashes of the 1990s and determines that they were in part the result of a complicated cultural legacy. The Korean legacy around power relationships stressed a strict hierarchy and a situation in which crew members could not—and dared not—contradict the pilot. As a result, the pilot did not receive feedback that could have prevented crashes.

Therefore, ignoring the double-edged sword of cultural legacies can make us unaware of our weaknesses and blind spots. To remedy this problem, people must become more aware of their blind spots and the effects of their cultural legacy. In so doing, they can appreciate what is positive about their culture and work to improve the blind spots or vulnerabilities that their culture imposes. Only by acknowledging the strengths and weaknesses of their culture can people push toward personal growth.