Because you like John McClane in Die Hard
Ash Williams is a houseware clerk at S-Mart and the Chosen One. See them in The Evil Dead.
Dominic Toretto lives his life "a quarter mile at a time", and he burns through those miles faster than anyone. See them in The Fast and the Furious.
The only thing Albert Wesker cares about is turning himself into a God. See them in Resident Evil Series.
Daring on a bike but haunted in his personal life, even Johnny Blaze isn't fast enough to outride his past. See them in Ghost Rider.
A no-nonsense pro, Agent K has dedicated his whole life to his job. See them in Men in Black.
There must be quite a lot of fellows who haven't got anybody to bring them tea in the morning. Bertie Wooster is lucky to have his valet, Jeeves. See them in Jeeves and Wooster.
Is there more to life than being really, really, ridiculously good looking? Derek Zoolander thinks not. See them in Zoolander.
Did he ever tell you the definition of insanity? Just wait, and this psychopath will do just that. See them in Far Cry 3.
It's easy for Brian O'Conner to fake his way into the world of extreme racing because he's been popping cars since his teenage years. See them in The Fast and the Furious.
Clank is the quintessential rational, intelligent robot sidekick. See them in Ratchet & Clank.
Big Boss is a disillusioned mercenary commander who wants to create a world for soldiers (and soldiers alone). See them in Metal Gear Series.