Because you like Jane Smith in Mr. & Mrs. Smith
With each reboot, Janet progresses more and becomes capable of human emotions. See them in The Good Place.
How lucky are we that Arthur Curry, the King of Atlantis, hasn't taken over the surface world? Very! See them in DC Extended Universe.
Victor Frankenstein can create life, so he's pretty awesome if he says so himself. See them in Frankenstein.
Bella Swan thinks of it as her job to help her parents and protect her friends, even though it often ends up the other way around. See them in Twilight.
Christian Grey is just as controlling in the bedroom as the boardroom. See them in Fifty Shades of Grey.
Keren Walker is a socialite looking to avoid work, keep a constant buzz, and be as snarky as possible. See them in Will & Grace.
Ofelia is face-to-face with the deadliest creatures of the underworld and completely unafraid. See them in Pan's Labryinth.
It's certainly easier to get great footage of crimes when you can guarantee they'll happen. See them in Nightcrawler.
Chaos is what killed the dinosaurs, and there's nothing Jason "J.D." Dean loves more than chaos. See them in Heathers.
Billy Batson is a troublemaking teen grappling with a pretty weird superhero identity crisis See them in DC Extended Universe.
A self-professed psychopath, James kills small animals for fun. After getting bored of that, he is ready for an ambitious murder. See them in The End of the F World.