Why did the Council of Trent accept some apocryphal books of the Bible but not others?

Trent simply reaffirmed the historic canon of the Bible after it had been challenged by Protestants. The same books Trent affirmed had been affirmed by councils and popes prior to Trent. The first recorded council dealing with the canon was the Council of Rome, which was held in 382 under the presidency of Pope Damasus. Later councils, such as Hippo (393) and Carthage (397) and the ecumenical council of Florence (1438), reaffirmed the canon issued by the Council of Rome.

At all these councils the canon that was proclaimed included the seven “deuterocanonical” books (1 and 2 Maccabees, Tobit, Judith, Baruch, Wisdom, and Sirach) and rejected 1 and 2 Esdras. Trent was not being inconsistent; it was reaffirming what the Church had always taught.