It seems like there are two kinds of things you can work on: right and wrong things. The right things bring you closer to your goals, the wrong things take you further away from your goals or nowhere at all. I firmly believe that one's ability to choose the right things to work on largely determines one's success.
Right and wrong things to work on must always be viewed relative to a goal. One thing may be the right thing to work on to achieve goal A, but the wrong one if you want to achieve goal B.
As a person, I am very enthusiastic and full of ideas. This may seem like two positive attributes, but the combination often leads to a lack of focus. For there are many good ideas, but not all of them lead towards the same goal. If you are too easily seduced by your abundance of ideas, you end up being unfocused, and this leads you very inefficiently towards your goal.
In my opinion, that's why it's important to spend time figuring out what your goals are. It sounds simple, but personally, I find it much easier said than done! For what is the actual dream scenario if you think 5-10 years into the future? This question deserves that you make an effort to answer it, and that you regularly revisit it to see if your actions align with your long-term goals.
The clearer you are on your goals, the better you become at determining what the right and wrong things to work on are in relation to achieving your goals.