This qualitative study sought to understand the reasoning of pre-service teachers through think-aloud interviews with teacher education students at the beginning of their postgraduate degree (six elementary and six secondary). Interviews focused on contextualised and challenging teaching scenarios with a range of response options previously confirmed through the use of situational judgement test (SJT) methodology. The authors' three-step analysis revealed seven concepts that highlighted the motivations and beliefs underlying the reasoning of pre-service teachers. Practical implications include professional development around decision-making during teacher education programs. Future research will explore the use of SJTs in developing key non-academic attributes for effective teaching.