Purgatory is defined as a for those who die in God’s grace but still harbor "imperfect purification". It is not a "second chance" at salvation, but a "finishing school" for heaven.
What Is Purgatory? | Catholic Answers Guide to the Afterlife Purgatory
To achieve the holiness necessary to enter the joy of heaven. It is often described as a "cleansing fire" that burns away the lasting defects of sin. Purgatory is defined as a for those who