Reliability is one of the most relevant software quality at-tributes. The literature o↵ers a variety of mathematical models -namely, software reliability growth models (SRGMs) -to estimate the reliability of a software product at a given time, as well as to predict the reliability that will be achieved as testing activities progress. One of the typical assumptions of SRGMs is the immediate debugging of detected faults. In reality, the impact of the debugging process cannot be neglected at all. This paper reports the results of a real-world case-study in which we analyze the debugging process of a Customer Relationship Manage-ment (CRM) system, and study its impact on SRGM-based reliability estimation and prediction.