As India's infrastructure continues to expand, ensuring the long-term performance of existing assets is becoming just as important as building new ones. While Structural Health Monitoring (SHM) has transformed the way engineers observe and understand structural behaviour through continuous data, the next evolution lies in using that information to answer a more strategic question: How much useful life remains? This article explores why Remaining Useful Life (RUL) is emerging as a critical metric for infrastructure management, helping asset owners, EPC contractors, and consultants move beyond condition monitoring toward predictive, data-driven decisions that optimize maintenance, rehabilitation, and long-term asset value.