This study investigates the degradation of electrodes during the resistance spot-welding process and its impact on both the welding process itself and the properties of the welded components. To simulate some of the most challenging degradation conditions, 1.5 mm thick electro-galvanized steel sheets were selected as the welding material DX51D+Zn275. For this type of material, the zinc coating tends to react with the electrode material during welding, forming a Zn-enriched layer, which accelerates electrode degradation. The experiments were conducted using an ELMA-Tech GmbH resistance spot welder. Short welding times were applied, with process parameters set at 70 ms, 12 kA, and an electrode pressing force of 2.5 kN. A total of 1100 welds were made under these conditions. Samples for mechanical testing and microstructural analysis were taken at 300, 500, and 1100 welds. A uniaxial tensile shear test was performed on the welded samples to determine the shear force at which failure occurred. Microscopic analysis was conducted using an optical microscope equipped for surface profiling and roughness measurements. Additionally, a scanning electron microscope (SEM) was used to analyze the electrodes after the welding process. Initial electrode roughness, measured as Rz = 1978.73 µm and Ra = 576.31 µm, displayed progressive wear and surface contamination, including zinc and burnt oil deposits that altered contact geometry, affecting electrode longevity. Roughness parameters evolved with weld counts and electrode wear correlated strongly with shear force. Chemical analyses have revealed the formation of a Zn-enriched layer and micro-cracking in electrodes, necessitating corrective machining after 1,100 welds to restore efficiency. These findings underscore the importance of managing electrode degradation to maintain weld quality and optimize industrial welding processes.