Because I don't want to be weak.
I was afraid to go to school like every kid, was afraid to ask permission from the teacher to go pee, later was afraid of reading out loud in front of the class. Once a time, this climber kind of structure was placed in the playground of our school. I was afraid of the even smaller climber and this was a huge one with more height. For days, I was only thinking about it and could not dare to cross it. One day, I just completed it, though it took me the whole recess period but I had crossed my fear.
From forgetting the speech on stage in front of thousand people to being alone on New Year's eve on a solo trip, I have faced many such instances where I messed up badly and ended up in humiliation. Fortunately, I did learn from them, did not get traumatized and did not give up.
Over the years, I built up this tendency to get out of my comfort zone and do the things even when a thousand thoughts have been running in my mind, most of being negative. It's not that I'm not afraid of losing but I'm more afraid of the guilt of not trying. Sometimes the things I do are not of much significance but I force my actions to overcome my thoughts so that I don't become weak. I have to control my thoughts and emotions and can't let them control me. I can be weaker than anybody but not me.