When you have high self-confidence, you are able to take risks and face new challenges with an open mind that you can achieve what your personal goals are. You believe in yourself that you will succeed and that you can make things happen. This allows you to do things that will direct you reaching your dreams and being the person you want to become. On the other hand, when you have low self-confidence, you are afraid of taking risks and this disables you to grab opportunities that will help you achieve things in your life. You are doubtful with your skills and capabilities and your mind is filled with negative thoughts.
Hence, even if you desire to be a better person in the future with a lot of achievements, you cannot take a step to reach that stage in your life. You are getting coward of realizing your visions.