Nobody likes a perfect character. It's really hard to make them likable. No weaknesses, no personality, flaws, and nothing to latch onto. I might get some flak for this, but Superman tends to come to mind. This isn't to say that Superman is a bad character. Obviously, he's been around forever, so there has to be something the people connect with. And you know, I think that what they connect with is the potential that Superman has when he's done right.
So many people I know think the character is boring. There's never anything at stake when he shows up. Now, I know that's not always true, but there's a reason for the sentiment. It's too easy to mess up with someone like Superman because there's so little for the average person to connect with. He's perfect.
So, when I come to new characters, I make sure that I don't make them some ideal version of themselves. Whether it's inexperience, cowardice, arrogance, over-confidence, inhibition, or any other of a myriad of character flaws, it's these little things that help someone identify with them. You need to know that when your character goes into a situation, there's a chance they'll fail. Hell, there's a chance they'll die.
But how do you come at these flaws? How deep do they go? A popular flaw these days is to give your hero some form of PTSD. I don't know that I land on one side or the other of that particular argument, but I feel like there are other choices that can work out better.
Probably the best advice I've been given for writing characters is to think about someone you know when you write. Now, that isn't to say that you just write your family and friends into a story and slap a bow on it. Think about the way they react to certain situations, both good and bad. Perhaps your protagonist can take inspiration from the way your father used to suppose his own expertise in matters he was unfamiliar with or your sister's habit of interrupting people. The character doesn't have to take everything from these inspirations, but if you can remember how people you know actually behave, you can write something believable. This counts for good quirks, too, so keep it in mind.
Be Excellent to Each Other
Keep your eyes open for my debut novel, The Paladin.