The reluctant hero is a heroic archetype found in fiction. The following as an apt summary of this archetype:
Another commentator notes, with respect to game design:
The reluctant hero is typically portrayed either as an ordinary person thrust into extraordinary circumstances which require him to rise to heroism, or as a person with extraordinary abilities who nonetheless evinces a desire to avoid using those abilities for the benefit of others. In either case, the reluctant hero does not initially seek adventure or the opportunity to do good, and their apparent selfishness may draw them into the category of antiheroes. The reluctant hero differs from the antihero in that the story arc of the former inevitably results in their becoming a true hero.
In many stories, the reluctant hero is portrayed as having a period of doubt after his initial foray into heroism. This may be brought about by the negative consequences of his own heroic actions, or by the achievement of some position of personal safety - leaving the audience to wonder whether he will return to heroism at the moment when he is needed the most.
Examples
In the movie Die Hard, Officer John McClane of the NYPD became a reluctant hero, when on Christmas Eve, East German terrorist Hans Gruber took over the Nakatomi Plaza, Los Angeles in an attempt to steal millions of bearer bonds. McClane, who was at Nakatomi Plaza, where his wife, Holly Genero was an employee, for the Christmas Party, was able to remain hidden from the group of terrorists, and was able to cause havoc, eventually spoiling Gruber's Christmas celebrations. Sgt. Al Powell of the LAPD who did not like using a gun after accidentally killing a young boy at a crime scene, also becomes a reluctant hero when he shoots and kills, the enraged terrorist known only as 'Karl'.
Robert A. Segal characterizes Arjuna from the Hindu epic The Mahabharata as a reluctant hero. Arjuna casts aside his weapons, fearful at the prospect of killing his kinsman during a civil war. Krishna then relates to Arjuna a series of arguments that convince Arjuna to go to war nonetheless.
A real-life example of a person described as a "reluctant hero" is Alvin York, a World War I soldier who was opposed to killing, but who was able to defeat a large number of German troops when this became necessary to save his fellow soldiers. York's achievement was then fictionalized in several movies, in which his stature as a reluctant hero was expanded.
In Star Wars, both Han Solo and (later) his son Jacen fit the characteristics of reluctant hero. Han is unwilling to ally himself with the Alliance to Restore the Republic for altruistic reasons. Twenty-six years later, his son Jacen is unwilling to fight out of fear that the galaxy will tumble into darkness. In the end, he saves his mother's life and wounds the Yuuzhan Vong Warmaster Tsavong Lah.
Spider-Man also fits the criteria of reluctant hero as throughout his career, Peter Parker constantly reevaluates his decision to become superhero. One of the most famous examples would be The Amazing Spider-Man issue 50, titled Spider-Man no more.
Actor Mel Gibson portrays reluctant heroes in the films Braveheart and The Patriot.