It's important for people to have goals. Goals motivate us to work hard. The possibility of achieving a desired goal makes the future a promising place. Goals provide direction and guide action. They help to establish a sense of purpose and thus make life more meaningful.
It is useful to define goals clearly so that we understand what we're working towards and we know when we've achieved it. It is possible, however, to be too specific. It's important to leave room for flexibility. If a person has a highly specific goal then there is only one acceptable outcome. Success is narrowly defined. This can cause people to pass up on other opportunities for growth that might also lead to a sense of achievement and personal fulfillment.
It is also important not to focus too intently on a given goal. If all of our efforts are focused on achieving one specific outcome we are likely to miss potential opportunities that present themselves. While it is important to focus on our goals in life it is equally important to be present and to participate fully in the world around us. If we achieve a desired goal only to realize that we've missed out on life then what have we really gained?