It is necessary to prepare for Mass. If we go to a soccer match we don't just play without a warm up. If we go to see a movie we don't arrive late we usually arrive to see the whole film. Why should Mass be any different. Preparation
should be given to the most precious gift that Jesus Christ has given to us. Here all the choirs of Angels are present, all the heavenly beings, only we cannot see them but they are with us in Spirit. Why come late? why rush in at the last moment, why
insult God? Arriving a few minutes before Mass begins is a good practice and it helps us to get into the right frame of mind for an encounter with our God and King.