You've heard it before: Running a marathon is far more mental than physical. A person's ability to run a marathon -- or do anything hard -- is more a reflection of his or her level of confidence than actual ability.
Your confidence determines:
- The size of challenges or goals you undertake
- Your likelihood of achieving those goals
- How well you bounce back from failures
When you're confident, you don't care how many times you fail, you're going to succeed.
And it doesn't matter how stacked against you the odds seem.