"Worship in 'spirit and truth' cannot dispense with a correct exterior rite. Thus, the Church has taken a long time to establish this rite. To produce a ceremony worthy of the sublime, everything must be considered important, each gesture, each vestment and each step. This is why respect for the rubrics is important. Rubrics have nothing to do with formalism or a cold legalism. The Holy Spirit created rubrics to become communicable thought the rite. The worship to God in spirit without an exterior rite is self contradiction. Where there is no rite, there is no adoration of God’s real presence, only chaos."
This is an interesting statement that sums up why we have a liturgy and the Holy mass.
I can't remember exactly who said it, but it is found in the O.A.T.H. piety book.