If we never stop and evaluate how we are leading ourselves, and where we are spiritually, emotionally, and mentally, we will find ourselves burned out, self-absorbed, or even apathetic to the call God has entrusted us with.
If you require that the fruit for your labors must always be visible and measurable, one of two things will happen, both of them bad: you will either lose heart and quit or you will become a manipulator of congregations.