One of the most challenging aspects of screenwriting is creating multidimensional characters that your audience can identify with, relate to, and be entertained by. Many times when I get hung up I ask myself, and maybe you do too, "Is my character likable enough to make the audience want to root for him/her throughout the entire story?" However, this video essay by screenwriting instructor, story consultant, and founder of Screentakes, Jennine Lanouette, explains why that may not be the question you should be most concerned about when dealing with characters.
There are plenty of characters from our favorite films (they're often the ones that made them our favorite in the first place) with qualities that we admire. They're witty, in control, selfless, deliciously evil, courageous -- there are so many things that make characters likable. And what I've found in my own experience is that this is the path of least resistance in storytelling -- the go to method for crafting characters: writing about people, qualities, personalities that we like.
But instead of being concerned with making your character likable, perhaps a better approach would be to make them sympathetic. This is more than a matter of semantics, though. Being likable and eliciting sympathy can be two very different things (though they can still exist in the same character à la the "every square is a rectangle, but not every rectangle is a square" rule), and exploring what makes a character sympathetic in the eyes of your audience as opposed to simply likable.
For example, I guess I like the guys from Dude, Where's My Car? -- they're silly, dumb, and completely unaware which is sometimes adorable -- but I really couldn't care less about their journey to find their car. Conversely, I absolutely loathed Edward Norton's character in American History X. Derek Vinyard represented so many things that are deplorable and disgusting about the dark side of humanity; he was racist, hateful, vengeful, arrogant, and wanted to recruit others, even his own kid brother, for his malevolent cause. However I stayed with the story, and I ended up sympathizing with him -- him. Why? Let Lanouette explain in her video essay below:
The point Lanouette makes on vulnerability is one of the most important factors in making your characters dimensional -- maybe because that's one way we as a human race relate to each other on a deep level. And I think that's the key -- vulnerability reveals the pain that caused the bad that hid the good. (Ya follow me?) Seeing vulnerability in characters is one of the reasons why we can potentially end up sympathizing and rooting for a disgustingly wealthy, philandering, hooker booty cocaine snorter like Jordan Belfort in The Wolf of Wall Street, because we can relate to his naiveté at the beginning of the film -- because at one time, he was just a good guy. We're all just "good guys", right?
Of course, there are so many other areas of storytelling that require your attention, too, and if you want a resource to learn more about what those areas are and how to master them, then you might want to take a look at the Kickstarter campaign Lanouette is currently running. She's putting together a series of eBooks chuck full of interactive media to help guide you through script analysis. Check out her campaign here.