Because you like Itzhak Stern in Schindler's List
Ethan Hunt's mission, should he chose to accept it, is to save the world from impossible threats. See them in Mission: Impossible.
Bucky Barnes used to be a good-hearted American soldier. Now he's the cold-hearted Winter Soldier. See them in Marvel Cinematic Universe.
The brilliant and well-adjusted Ender Wiggin is being groomed for the next generation of military leaders to fight alien invaders. See them in Ender's Game.
Sokka is the group's self proclaimed comedian, occasionally he'll even make people laugh! See them in Avatar: The Last Airbender.
Rose Tyler may have not done too well in school, but she's certainly holding her own in space. See them in Doctor Who.
When his friend goes missing, Lucas Sinclair is ready to fight. All of the Dungeons and Dragons is really paying off. See them in Stranger Things.
This barber doesn't cut hair. Sweeney Todd sends his clients down a chute to be baked into his partner-in-crime's pies. See them in Sweeney Todd: The Demon Barber of Fleet Street.
Just call Jeff Lebowski The Dude. Or His Dudeness, Duder, or El Duderino if you're not into that whole brevity thing. See them in The Big Lebowski.
With an undeniable sense of adventure, Huck Finn is an expert at getting into and, more importantly, out of sticky situations. See them in The Adventures of Huckleberry Finn.
Faith balances her adventurous thrill-seeking attitude with a righteous passion for justice. See them in Mirror's Edge.
We're all puppets. Dr. Manhattan is just a puppet who can see the strings. See them in Watchmen.