What does this quote mean?

"When obstacles arise you change your direction to reach your goal, you do not change your decision to get there."

The quote's meaning is when working towards your goal, many problems will arise. When you face these problems, you shouldn't question if your goal is worth the work to solve these problems, but instead keep moving forward, by going a different way.

To put this in an example, lets say you are in a car, driving towards your friends house, but the highway is in a traffic jam and instead of the 20 minutes it would have taken you, it will take 2 hours. Instead of deciding not to go to your friends house, you should take an exit that will also lead to your friends house, but will take 40 min instead of 20.