I believe a little green alien said it best....
"Do or do not, there is no try."
We are what we think we are, and if you think you can accomplish something, you will.
The samurai were very intuitive about such things, putting everything in focus as life or death, throwing away their lives without thought. In the Hagakure it even talks about living your day as if you were being smashed upon rocks, impaled by hundreds of arrows, or ripped apart by gunfire. I never thought it possible, but my current job and the split-second decisions I've had to make so far that saved not only mine but others has given me a perspective that fits with this mentality. If you even have one thought of failure before the lift, you are done. If you go into the lift with the mentality of moving a mountain and succeeding, even if the mountain doesn't move, you have achieved the next step.