Yep I said that right. Stewart interviewed JK Rowling and amidst random discussions about magic and wonder of monarchy, they started talking about writing and what makes a good character.
You can watch the whole video here: Jon Stewart Interviews JK Rowling, but the crucial part comes at the end when Stewart says "Without Kryptonite, you've got nothing."
|His underwear is on the outside and we still love him! Source|
Enter kryptonite. The glowing green substance that renders the man of super to a powerless puddle of mush.
I think most writers understand that readers are not going to accept a practically-perfect-in-every-way character unless you're Mary Poppins.
However, a lot of writers fail to utilize their characters flaws to the maximum extent. If Superman knew where all the kryptonite was stored and only had to avoid those warehouses in order to beat the bad guy, the story would be boring. But if the bad guy forces him to go through a gauntlet of the green stuff to save his precious Lois. Well...now we got ourselves a story.
Once you've given your character a flaw, force them to overcome it in order to "win". Is your character forcefully independent and driving everyone away? Make him team up with an unlikely partner in order to solve the mystery. Is your protagonist self-centered? Force her into a situation where she has to make a sacrifice for others in order to beat the antagonist.
Flaws make our characters more realistic and help our readers relate to them, but don't write 'em up and put 'em on a shelf. Make those flaws work a double shift and add some extra tension to your novel.
Take charge of the kryptonite!