What is Deficit Theory

In an attempt to explain deficiencies in lower socio-economic students’ success rate, some researchers postulated that failure occurred due to insufficient verbal foundation in the home for success. The deficit theory proposed by Eller, 1989 suggested that working-class children have an inadequate command of grammar and vocabulary to express complex ideas. Deficit theory explains why students fail in using English. They have:

1. Poor linguistic ability
2. Limited vocabulary and limited range of grammatical constructions
3. Inadequate communicative ability with persons from different language background
4. Lack of coherence in their presentations.

As a result, students experience psychological problems and feel incompetent in class. Thus the theory emphasizes the importance of environment in language learning.