Teacher motivation is a critical yet often underexamined factor influencing literacy instruction and students’ reading engagement. While literacy reforms emphasize skill development and assessment outcomes, less attention has been given to the motivational forces sustaining teachers’ commitment to literacy teaching, particularly in resource-constrained and culturally diverse contexts. This qualitative study explored how teachers experience and sustain motivation in literacy instruction, how motivation shapes classroom practices, and what contextual factors support or constrain sustained engagement. Data were collected through semi-structured interviews and document review and analyzed using thematic analysis. Findings indicate that teacher motivation is strengthened by student engagement, perceived instructional effectiveness, intrinsic fulfillment from student success, and professional learning opportunities. Motivated teachers foster engaging literacy environments through enthusiasm, responsive pedagogy, and culturally relevant practices. However, motivation is mediated by contextual realities. Supportive school environments enhance motivation, whereas socioeconomic disparities, resource limitations, large class sizes, and policy pressures constrain its sustainability. The study positions teacher motivation as a relational and socio-culturally mediated construct essential to sustaining effective literacy instruction.