What is not being afraid of making mistakes?

People talk about what real courage is all about and explain that it means not being afraid of making mistakes. But all it does is make you wonder how to tell when you about to make a mistake and still want to do it. I just imagined a situation like that:

You have a goal. Sometimes you are working, and when you are free, you think about that goal always at the back of your mind. And some day, opportunity disguised as your friend knocks on your door and shows you 'one' way to your goal. Like all goals, the path is not easy. It's simple but not easy. But since you have nothing better to do in your life than to achieve your purpose, you pursue that goal. On the way, you have to convince someone to let you pass their property, borrow something they have or get them to do something for you and you would pay them for it. They refuse to do it at first. You get angry. There have been countless times this has happened in your life – people refusing to do what you ask them to do, even beg them to do. And still, you argue, request, order, yell, beg or simply ask them to do something for you, knowing not every time whether or not they are going to help you. But not always you are going to be not angry with them. Nevertheless, you are aware that the angrier you get, the less there is chance of persuading them. And so, there are many moments you are angry at them and are arguing about why they should do your bidding.

There it is. You are fully and consciously aware that you are making a mistake by getting angry and arguing. You know you are helpless. You know that you are pushing them away by giving way to anger. There's the mistake. But you see no other way around, because at that moment, that's the only way to your goal you are aware of. So, you make that mistake knowingly. You are not afraid of committing the mistake of getting angry at the person you want to help you. Sometimes it works, sometimes it doesn't, because not everybody is the same. Some people are intimidated and do as you say. Some get angrier and throw you out or call the police. On the off chance that they might be intimidated, you let yourselves get angry.

There you go. You just realized that if you are not afraid of making a mistake, courage and success will be yours.