Objectives: Individuals with post-traumatic stress disorder related to childhood maltreatment (PTSD-CM) show limited response to treatment on pre-post-symptom measures. While a nuanced understanding of nonresponse is crucial for improving treatment, quantitative measures may not fully capture clinically meaningful processes of change from the patients' perspectives. We therefore explored how individuals with PTSD-CM who showed no or limited numerical improvement after trauma-focused psychodynamic psychotherapy (TF-PDT) experienced change. Design: This qualitative study was embedded in a large randomized controlled trial on PTSD-CM (DRKS00021142). Method: From 75 qualitative post-treatment interviews, we purposively sampled eight TF-PDT recipients meeting criteria for numerical nonresponse, defined as current PTSD diagnosis and less than 50% reduction in the Clinician-Administered PTSD Scale for DSM-5 (CAPS-5). Client Change Interviews were analysed using Critical-Constructivist Grounded Theory. Results: We derived two clusters (‘Progress—A Double-Edged Sword’, ‘When Building Trust Collides with the Therapeutic Framework’) and one overarching core category (‘Unfinished Business’), which captured a dialectic process. Within a responsive therapeutic relationship, patients began confronting their relational trauma, experiencing relief, increased emotional regulation and hope. However, this very engagement surfaced emotional challenges that exceeded what could be addressed within the limited therapeutic framework, leaving the process meaningful but unfinished. Conclusion: What is often labelled as numerical nonresponse in PTSD-CM may reflect a dynamic interplay of emerging improvement and emotional distress that needs more time to unfold. Moreover, the results underscore the value of integrating qualitative, patient-reported outcomes into treatment evaluation and relationship-focused treatment tailored to patients' individual needs.