The present study can clarify that the subgroups considered (social class, migration background, gender) differ in their structural effects regarding the explanation of reading competence. Although the enhancement of known factors, such as reading motivation, benefits all students, there are still significant differences or varying weights in terms of promoting reading competence. The study shows that the well-intentioned encouragement to read not only counters motivation and the development of a reading-related self-concept but also directly reduces the development of reading competence, particularly among adolescents from a socially disadvantaged background.