Dear Jamie,  

It all depends on why your spiritual director thinks you should wait. As a general rule if there is something concrete and important that you still need to work on before joining the seminary it is better to wait. If you are not perfect, but everything is 'normal', then it is best to move - you can't wait until you're perfect before taking the step.  

What would be some examples of points that it would be advisable to work on before following your vocation? Well, if you are all fired up with thoughts of the vocation, but you are chronically irresponsible in your ordinary duties; if you still have some bad habit to overcome; if you have debts you have to pay off; if you are ill and need convalescence; if you have absolutely no control of your moods; if your prayer, vocation insight, spiritual life are based on emotions only... All of this has of course to be taken in relation to your age. You would expect more of a college man thinking of the priesthood than a high-schooler thinking of the minor seminary.  

If you feel uneasy about what your spiritual director is advising you, ask him. Remember, the role of a spiritual director is not to tell you what to do 'no questions', but to help you discover what God is asking of you so that you can understand, accept and do it. You have to actively participate in the spiritual direction and contribute your ideas and reflections. He needs to know what you perceive in prayer, what your inclinations are, what you honestly believe God is asking of you and why. His role is to shed light on these things, test them to see if they are valid and if they have the signs of coming form God, and let you know why if they don't. He is trying to help you understand and follow the ways of God.