Well Begun and I'm Done

I have a very deep character flaw. I've struggled with it for years and years and years. Sometimes I fight tooth-and-nail against it. Other times, I just give in and indulge it. I typically begin a project, get part-way through it, and then I just stop. I have left a trail of half-written stories in my wake. Sometimes, years later, I'll open a text file with a promising name only to be met with a blank page.Some of my old short stories had just started to get good before I abruptly stopped writing, sometimes in the very middle of a sentence. I don't know if it's my A.D.D. or just my personality, but it's something I don't like about myself.
The one rare exception to this pattern is my dalliance with Magic: The Gathering. Of all the hobbies I've ever attempted, this is the longest running at three years. Of course, my interest has ebbed and flowed, but lately it seems as though this might be the first hobby to have any kind of permanence. I reckon it's because there's just so much to do. I started off playing a Red Green creature deck, switched to a Black Blue Infect deck for my first tournament, then went mono-red for Legacy, back to Infect (Black Green this time), and finally I've settled on Mono-Red Goblins. Every few months I'm glued to my monitor, waiting for a new card to be spoiled. I've built a casual mill deck, an aggressive Red Green deck built around Bloodbraid Elf, and a Red Black White Commander deck that I'm thinking of changing to a Red Black Zombie deck. On top of all of that, I've started building another tournament deck for Modern and I've slung together a mono-Red deck for Standard (don't laugh). I've studied other decks, watched tournaments online, and have even gone to a Grand Prix!
I say all this to illustrate why I think Magic is here to stay in my brain; variety. I just can't get bored with something as big, elaborate, and complex as this. There's just too many interesting things to do! If you like games featuring complex interactions between player skill and sheer luck, Magic is for you. I know it is for me.
So, that said, I'm starting to feel like I'm losing interest in my story. I wrote a brief back-story for one of my characters and am extremely unhappy with it. It seems that I have taken my character and crammed him into a shoe-box. I wanted him to be a noble but free-spirited individual with violent past, but his childhood doesn't seem to lead to that. It certainly leads to his violent nature, but not the nobility I wanted. As it stands, the back-story would lead him (it seems) to be a petulant cliche always on the verge of either tears or violence.
What this means is that my character is very boring. He's uninteresting because, at the moment, he's a mannequin, a lifeless dummy put into different poses depending on the needs of the story.
And this is the problem with a lot of current fiction; their characters are mere cliches because, in the author's mind, they're not important. The world is! It's all about the cool scenes and plot twists. It's about using big words and big phrases because the author be praised for his knowledge of words archaic or esoteric (I've just been struck with how archaic 'archaic' is and how esoteric 'esoteric' is). But, a book would be boring if it was just descriptions of places and you needs characters for plots, so in comes the woman who is just as strong and determined as any man (as if men are the only ones with strength and determination) or the precocious child who is willful and rebellious (a character introduced so that we chuckle because bratty children are cute) or the male hero who is in touch with his feminine side and abhors the kind of violence he is practically driven to (as if knowing how one feels and wanting to destroy one's enemies are mutually exclusive). Unfortunately, I have fallen into this temptation to take the easy way out. I wrote the hero of my story as a tragic figure and (according to the bio) should grow up to be a dark and haunted character, instead of the lively man who is fiercely loyal to his crew, friendly towards those in need, and soaked in blood.
Of course, the cure is easy; I'll go back and re-write it. I'll change events in his life until I can find a trajectory that gets him where I want him to be. It'll take work, but it's worthwhile work. But, anyway, I thought it worthy commenting on the process of developing a story for a character, instead of a character for a story.