My reasons were manifold. For as long as I can remember, I've been overweight. I'm 26 now, and until last year, I'd been a size 18 since the age of 18.
I was out of a job at the beginning of 2014 and ended up working back at somewhere I'd worked before and vowed never to go back to. The pay was minimum wage and after paying bills and debt payments, I could barely afford to feed myself, so I subsisted on a lot of frozen and processed crap. I put weight on and my size 18s started feeling tight. I lost all confidence, and though I knew I needed to do something, I couldn't find the motivation.
Then I met my now-boyfriend. He told me about how he'd woken up one day, looked in the mirror and hated what he saw, so he decided to do something about it. He changed his diet completely, started working out, and lost 4st. I thought, "Why can't I do the same?" After we figured out that we were made for each other, and it turned out that he has kids from a previous relationship, I also realised that one day I'll be a part of their lives and so it's my job to be in a good place health wise so that I can be a good role model and not give them any reasons to worry.
I've now lost nearly 3st, dropped to a size 14/16 top and size 14 bottom, with just over another 2st to go. I don't remember ever being this clothes size, and on the days where I've got my head on straight, it feels really good. Onwards and downwards.