Everyone sets tasks for themselves that are worth it to complete. Even though from time to time it seems that you are doing something so difficult that it is impossible to complete.
The best comparison to see how much focussing your efforts helps is by looking at the sun. The sun brings heat to everything around it, from burning everything close to it, to heating up planets far away. Even though it burns everything close by, luckily it doesn’t burn things on earth, or does it? When the sunshine is being focussed through a magnifying glass you can start a fire on a leave or a paper. All the heat is entering the entire surface of the lens. But the power output is being sent out through one point only.
Concentrate all your thought upon the work at hand. The sun’s rays do not burn until brought to a focus. – Alexander Graham Bell
Setting a goal for yourself teaches you to focus on the important things. Having something to aim for means that you put priority on it in comparison to the activities that you would normally do if you wouldn’t have a goal. An example of focussing your efforts is learning a new language. The more time you spend in the other language the more you will learn and the better familiar you will be with the language.
The focus doesn’t have to lie in one specific area of exercise. With language for example you can start listening to the radio in a different language, read a book, use a language app, speak to people and so much more. The important thing is that you do something that aims at working towards your goal. Instead of only completing your goals at the same time you are building your character and receive respect from the people around you. They see all the hard work you put in to achieve what you wanted.