What makes you keep on?

I was thinking of that today while I was walking. What makes you do what you do? What makes you stay on that treadmill an extra mile when you are done. And you hate ever single minute of it? What makes you drag yourself outside on a 10 degree day when you are cold to get a walk in. Exercise is so mental. Getting off the couch. Starting. Keeping on. It hurts, so quit. What makes you stay in there and fight? What makes you keep on. I think the more I try the more I learn about myself. I must want it whatever it is. I must to be not drinking soda still after 13 days. The headaches are gone so it's all good.It feels different this time perhaps training for this helps. Who knows I sure hope it stays with me this time.