Many condemn the Church because of it's mistakes and failures. Here is what I should say:
The Church is Holy even if it is composed of sinners and saints. No matter how it's teachings and laws are poorly conveyed and implemented, the teachings and laws shall remain undefiled for they are universal and works of the Holy Spirit. No matter how sinful are it's people even to the extent of priests and bishops, it shall remain Holy because it is founded by the Holy himself, Jesus Christ.
Holiness is different from perfection. The Church is holy yet still not perfect because it is always tested, made to last till the end of times in the midst of persecutions and tribulations. When the time comes, it shall be made ready to become the Bride of Christ (meaning communion of Christ's people with Christ himself).
In my opinion, although I am nobody compared to the Holy Fathers, I'm thankful for the criticisms they throw to the Church because these things can help the Church to prepare it's wedding with Christ in the end of times.