Steven Covey, in his book First Things First, suggests reasons why people waste time. He broke time management down into four quadrants. This leads individuals to spend more time in non-urgent unimportant escapes like drinking alcohol, television, gambling, and other time consuming vices. It means make time for the things that are really important. This entails prioritizing and planning.
Many people are opposed to planning, because they say it destroys their sense of spontaneity.
If spontaneity is taking you where you really want to go with your life, then you do not need to worry about time management. For the majority of us, spontaneity means waiting for a break in the tedium. Planning eliminates the tedium, and provides movement into a productive life. It does not mean you will not be able to do the things you want to do. It means now you will plan for leisure, work, school, studying, relaxation, relationship building, and any other worthwhile pursuit.