Background: For the majority of cataract patients, uneventful phacoemulsification resulted in a good visual outcome. However, some patients came unhappy with their results even with perfectly done cataract surgery. These unexpected bad outcomes were so frustrating both for surgeons and patients. As a result, patient happiness is the end goal to evaluate and improve our provided health service. Aim of the study: to describe the prevalence and causes of unhappy patients after uneventful phaco-emulsification in our practice in Suez general hospital. Patients and Methods: This prospective cohort study was conducted at the Ophthalmology Outpatient Clinic of Suez General Hospital on 100 patients that underwent uncomplicated phacoemulsification in the period from February to April 2024 with the same surgeon and was randomly selected from the theatre list and records after 2 months from surgery time. All selected patients were recalled and subjected to a face-to-face questionnaire to measure their satisf-action level. In the dissatisfied group, all patients were subjected to full history taking, visual acuity assessment, anterior and posterior segment examinations, ultrasonography, and optical coherence tomography. The data collection tool PSQ-18 was used to evaluate patient satisfaction. The validated questionnaire was done and completed by the researcher 2 months after the operation and was translated by the forward-backward method. Results: Among the patients that were chosen, 70% were satisfied and 30% were dissatisfied. The PSQ-18 questionnaire score showed that time spent with the doctor had the best scoring, followed by communications, interpersonal manner, financial aspects, technical quality, accessibility and convenience. The overall satisfaction of patients was (4.0 ± 0.6). Regarding scales of dissatisfaction, dissatisfied patient had significantly lower mean score in financial aspect, convenience and general satisfaction score (P<0.05). Regarding causes of dissatisfaction, the technical issues of the surgeries was prominent, and the causes of unhappiness were as following: residual refractive error constituted (43.3%), dysphotopsia (30.0%), ocular surface disorders (16.7%) and posterior segment disorders (10.0%). Conclusion: Physician accessibility and technical quality showed the most evidence, whereas the physical environment and economical aspects had the least link with overall satisfaction. We ought to pay closer attention to our disgruntled patient who underwent a straightforward surgery in order to identify the reasons for his dissatisfaction and enhance the quality of care we offer.