I was having second thoughts about doing it and at first was thankful each zipline was over. But the more I did it, the easier and more fun it got.
This is true for many other things in our lives. If you are facing a challenge and it seems impossible to accomplish, break it into smaller steps. If you are facing debt, one way is to determine a reasonable amount you can put towards the debt each month. This will give you an idea of how long it will take you to pay it off. It is sometimes easier to accomplish a goal when you have a timeframe for it. If you do not accomplish your goal by the deadline, just extend your deadline instead of giving up.