Because you like Michael Bluth in Arrested Development
Emmet Brickowski is so upbeat it's not even human. Everything is AWESOME! See them in The Lego Movie.
Steven Universe is an excitable youth who likes junk food and trying to save the world. See them in Steven Universe.
When Jessica Jones is not throwing back drinks, she's taking down bad guys with her strength, detective skills, and foul-mouthed insults. See them in Marvel Cinematic Universe.
An All-American football player, a ping pong star, and a freakishly determined runner, Forrest Gump has a ton of stories to tell. See them in Forrest Gump.