I’m going to try to answer this without comparing the Traditional Latin Mass to the Novus Ordo. That way, maybe no one will enter this thread to argue.
The primary reason that I attend the TLM. exclusively is the prayers. The Prayers at the foot of the Altar where the priest prays that he will be made worthy to pray the Mass…myself that I made also be made worthy to attend it. These prayers show the absolute humility of the priest & the laity.
A good example is the double Confiteor, one to absolve the sins of the priest & one to absolve my own. These end with the priest praying "Take away from us our iniquities, we beseech Thee, O Lord; that, being made pure in heart we may be worthy to enter into the Holy of Holies. Through Christ our Lord. Amen.
Then, of course, there is the prayer before the gospel. The priest prays:
"Cleanse my heart and my lips, O almighty God, Who didst cleanse with a burning coal the lips of the prophet Isaias; and vouchsafe in Thy loving kindness so to purify me that I may be enabled worthily to announce Thy holy Gospel. Through Christ our Lord. Amen.
Vouchsafe, O Lord, to bless me. The Lord be in my heart and on my lips, that I may worthily and becomingly announce His gospel. Amen.
As I’ve said before, the TLM. is a Mass said for sinners, by sinners &
I love watching & hearing the priest working out his own salvation “in fear & in trembling”, while he & I are doing the same re my own salvation. . It is as if I’ve entered into a very private place & am partaking of the holy relationship between Christ & one of the men he called By being allowed to enter into this, I become one with the priest. That isn’t a really good illustration of what is happening in this Mass, but it’s the best I can do…in translating my thoughts & feelings into words.
Now, for some secondary reasons…the priest facing the altar…makes it quite clear that he is praying FOR me, not AT me or TO me.
The Sacred Silence that many of you have mentioned is also very important to me. I cannot meditate well, without it.
The humility shown once again as we kneel to receive Our Lord, not allowing any part of our body to unnecessarily touch His Body. Many will argue that this is just a pious practice, that one’s tongue is no holier than one’s hands & that is true. However, pious practices such as this one are unique to Catholicism & must not be lost.
I could go on & on, but I won’t. I’ll just add that as the Last Gospel begins: “In principio erat Verbum, et Verbum erat apud Deum, et Deus erat Verbum… (In the beginning was the Word, and the Word was with God, and the Word was God…)” & proceeds to what I believe to be the most true & the saddest words " He was in the world, and the world was made by him, and the world knew him not & the Leonine prayers after Mass. In my parish over half of the Mass participants stay & pray their own private prayers of Thanksgiving for the Mass.