The Apocrypha books were not added to scripture because of several reasons
1. They contain historical and geographical inaccuracies and anachronisms
2. They teach doctrines which are false and foster practices which are at variance with inspired scripture
3. They resort to literary types and display an artificiality of subject matter and styling out of keeping with inspired scripture
4. They lack the distinctive elements which give prophetic power, poetic and religious feeling
Of course this does not mean the books are useless. Many of them have noble sentiments and writings but they were simply not from God.
5. No canon or council of the Christian church for the first 4 centuries recognized the Apocrypha as inspired
6. Many of the great Fathers of the early church spoke out against the Apocrypha
7. The Jewish scholars of Jamnia did not recognize the Apocrypha
8. Luther and the Reformers rejected the canonicity of the Apocrypha
9. Since this time, there has been no serious questioning of the 27 accepted books of the New Testament