Quality change refers to the improvement, enhancement, or alteration of the overall standards of a product, service, or experience. One synonym for quality change is "upgrading," which suggests the act of taking something to a higher level of quality. Another term that could be used is "refinement," indicating the process of enhancing or polishing something to a higher standard. "Development" is also a suitable synonym, implying the continuous improvement of a product or service through ongoing research and innovation. "Transformation" and "evolution" suggest a significant change in quality, structure, or nature, often leading to a superior outcome. Overall, there are various terms that can be used to effectively communicate the idea of a quality change.