I often heard people always said, "Don't be thinking negatively, it's not good for you" or "If you always think negatively, you will be stressed". That is true. Every time I think negatively, I always ended up with repentance.
When I was in Senior High School, I never joined a competition or an event out of school. The reason is I always think that I am not able to join the competition and I am not suitable to be nominated. This thought led me to not participate in that activity.
I realized that negative thinking can impact the actions I take. Since then, I started to change negative thoughts to positive thoughts. I give myself verbal affirmations such as "You are awesome!" or "I know you can do it, try it, and never give up", and so on. This words make my day. I got my confidence and I dare myself to take part in competition and various activities. These experiences taught me a lot.
That is why we should think positively. Positive thinking doesn't mean ignoring negative possibilities. It's just accepting that we are required to focus on what we can control.