People I RP with, people who read my stories or just people I talked with about characters will probably know that my characters are far from flawless, sometimes up to the point of being complete trainwrecks.
I think it's an important thing to make mistakes. They teach you, often the hard way. Some can be corrected, some can't. They have an impact. I like that in characters.
I see a lot of RPers, writers, who are super afraid to let their characters make mistakes. They either make the character solely a chewtoy of fate or just justify every single mistake the character makes.
It's okay sometimes, because sometimes fate just comes and fucks your shit up like the bitch it is (some of my characters have had their fair share of that as well, not denying that in the slightest), but not always. Sometimes the fault is your own.
For me, the mistakes my characters make are part of their growth. Wether it's one that affects many lives, or just two in the case of a bad romance, to more or less quote Lady Gaga; it had impact. If you fuck up so badly many lives are affected or even ended, what do you do? Run away? Hide? Own up? Try to fix that shit? And if it's just a relationship gone horribly, it may not be much to the world, but to those two people or at least one of them it might mean the world. And that's pretty fucking interesting. How do you recover from a breakup? You could eat a whole can of Ben and Jerry's, you could drink until you pass out, hop straight onto the next relationship or talk about with your friends until you all fall asleep at four AM in the morning.
I also like it when other people's characters have made their mistakes. A character that is never at fault is quick to feel like cardboard, because it's humanly impossible to not make any mistakes whatsoever, so characters that don't really bore me. Even if you are a trouble magnet; I'm sure you're also perfectly capable of fucking up on your own.