Objective: This study aimed to explore the actions taken by patients who had been admitted to an acute care Queensland hospital and experienced dissatisfaction with service delivery. It is proposed that before complaints can be used as part of a strategy to inform health service improvement and ultimately ensure patient safety, an understanding of the effectiveness of the complaints handling process from the patient's perspective must be gained. Methods: In-depth qualitative interviews using a phenomenological exploration were undertaken. The theoretical framework supporting the thematic analysis of the interview data was drawn from Lazarus's cognitive emotive model of coping. Analysis of the research data, aided by Leximancer software, revealed a series of relational themes that supported the interpretative data analysis process undertaken. Findings: In 16 interviews, the study outcomes identified that 15 of the participants did not voice their complaint at the time of the event, but after the event, they stated they wished that they had reacted differently and complained at the actual point in time that they were dissatisfied. The themes that emerged that reflected potential lost opportunities included issues with ineffective communication, being treated with disrespect, inconsistent standards of care, perceptions of negligence, and lack of information about how to make a complaint. Conclusions: Our findings suggest that health-care professionals should take a more active role in identifying and responding to patients who are experiencing dissatisfaction but are not actively complaining. This level of vigilance and responsiveness will ensure opportunities to improve health service delivery, and patient safety are not lost.