Few reasons:
1. I have a bad knee due to breaking it several times. (The first time I broke it I was 12 and walked on it for about a week before I was taken to the hospital.)
2. My daughter. That being a big one, she loves going out and doing things. It's getting harder for me because of my injuries from a car accident and my weight compounding that issue.
3. Recently my fiance of 4 years (6'4 and almost 400 pounds) told me I was too fat for him and left us. Well recently left us, he always got on me about my weight.
4. I'm tired of being depressed and feeling completely hopeless about my weight. I don't want to sit around waiting to die.