Why do we even set goals? why don't we just simply work spontaneously and act on our instincts? Why don't we just do what comes next to us? Why don't we simply try to do our best at the moment?
These are all very valid questions about goals setting and most people don't set goals for one of these reasons. They believe that if they keep doing their best, they will get where they want to go. This is is fine but if you don't have a specific time-bound goal then you don't know if you are moving in the right direction with the right pace or not.
When we sit down and spend some time setting specific goals in different aspects of our life then we are committing ourselves to those goals. We are also setting these goals based upon our mission/well being in life. When we set a specific goal of saving a certain amount of money every month then you are committing to saving that much. You will also have to figure out how can you reach that goal every month. Which areas you can cut down on spending to save that much money. These are all very specific steps to achieve a specific goal. It wouldn't be possible if you just wanted to save the most you can as you are not going to come up with a plan to cut spending to meet your specific goal.
Let's take another example: let's say you set a goal to meet your ideal life partner in the next 6 months. To fulfill that goal you will have to find the time and create a plan to meet this person. You will have to explore different options to meet like-minded people. You will have to be accountable to that plan and do something every day and every week to move towards your goal. You will have to stretch yourself to get to your goal. That wouldn't be possible if you just leave it to the universe to find someone for you. Of course, there is no ultimate guarantee that you will be successful in your plan but you are likely to meet fun people in the process and learn a lot more about your future life partner by meeting many people that wouldn't be a good fit for you.
You need to set goals in all major aspects of your life- Financial, Relationship, Career, Health, Self-awareness/Personal Growth, Family/Friends/Social. Once you go through this goal setting exercise then you will see remarkable improvements in all these areas of your life. Just the process of setting goals is an exploration of your best self. It helps you visualize the best life you can possibly have.
The process of moving towards your goals is self-satisfying. In the end, it is not even about reaching all your goals but enjoying the journey in trying to achieve your goals. Happiness is only an outcome of the process of moving towards your goals.