Sometimes (often), people are too hard on priests.
There will always be the human element.
And God wanted it this way as He chose men, not angels.
"But although God is the author and dispenser of the Sacraments, He nevertheless willed that they should be administered in His Church by men, not by Angels. To constitute a Sacrament, as the unbroken tradition of the Fathers testifies, matter and form are not more necessary than is the ministry of men."
-Catechism of the Council of Trent
The Ministers of the Sacraments