Catholics venerate relics of various saints. All saints are humble and would want to give glory to God alone. Therefore, they'd rather we go to the Lord directly and not center upon them. There is a fine line to be drawn here. It is perfectly fine to let the saints inspire us to increase our love for God, but we must never grow attached to any saint to the point that we lessen our focus upon the Lord. If you seek to attain union with God, it is best that you go to him directly and let absolutely nothing distract you along the way.