Where do we find the "defects" in the soul from sin taught?
414 Q. What is Purgatory?
A. Purgatory is the state in which those suffer for a time who die guilty of venial sins, or without having satisfied for the punishment due to their sins.
Why do you persist in citing the Baltimore Catechism as being the definitive expression of Catholic doctrine when it has been explained to you many, many times that the purpose of this Catechism was only to establish initial familiarization with the concepts and language of Catholicism to a juvenile audience? That was a rhetorical question because I know the answer; it is to deceive and to diminish the Church. The actual Catechism of the Catholic Church teaches:
III. THE FINAL PURIFICATION, OR PURGATORY
1030 All who die in God's grace and friendship, but still imperfectly purified, are indeed assured of their eternal salvation; but after death they undergo purification, so as to achieve the holiness necessary to enter the joy of heaven.
1031 The Church gives the name Purgatory to this final purification of the elect, which is entirely different from the punishment of the damned. The Church formulated her doctrine of faith on Purgatory especially at the Councils of Florence and Trent. The tradition of the Church, by reference to certain texts of Scripture, speaks of a cleansing fire:
As for certain lesser faults, we must believe that, before the Final Judgment, there is a purifying fire. He who is truth says that whoever utters blasphemy against the Holy Spirit will be pardoned neither in this age nor in the age to come. From this sentence we understand that certain offenses can be forgiven in this age, but certain others in the age to come.
1032 This teaching is also based on the practice of prayer for the dead, already mentioned in Sacred Scripture: "Therefore Judas Maccabeus] made atonement for the dead, that they might be delivered from their sin." From the beginning the Church has honored the memory of the dead and offered prayers in suffrage for them, above all the Eucharistic sacrifice, so that, thus purified, they may attain the beatific vision of God. The Church also commends almsgiving, indulgences, and works of penance undertaken on behalf of the dead:
Let us help and commemorate them. If Job's sons were purified by their father's sacrifice, why would we doubt that our offerings for the dead bring them some consolation? Let us not hesitate to help those who have died and to offer our prayers for them.
The Baltimore Catechism is known for vague and inaccurate statements like this. What they mean is that the Purgatory purges the souls of those who failed to do their penance for the confessed sin.
Where do we find the "defects" in the soul from sin taught?
Why, in 1 Cor 3:9-15. "If any man's work burn, he shall suffer loss".