Why limit yourself?

How often do you believe that you can or can not do something. You may have tried and tried and then believe that you can't do it so you stop trying. You are usually right at a breakthrough point when you quit. There is NO one who is successful at what they are doing who has not failed over and over again.
Why do some succeed and some quit? The ones who succeed believe they can be successful or achieve what they are going for, and when they come across something they can not do they try again. I have experienced this many times thru the years.
You would think after you have succeeded at what you are doing or where you are going that you would not have those trip ups or challenges again. Well that is not true, it is a continual part of your journey. In fact they become bigger challenges for you to overcome. Each time we learn a little more, but the biggest thing you learn is that you do not quit. That is the ultimate failure.
So remember that your limitations are in your head not your capabilities. Why limit yourself???