Stablecoins, a type of cryptocurrency tethered to real-world currencies, have garnered attention in the cryptocurrency sphere. Despite being designed for price stability, as seen in the 2022 UST case, this is not always guaranteed. To prevent such incidents, understanding the vital factors behind stablecoin's success is crucial. This article examines the case of USDT, a prominent stablecoin. Preliminary findings indicate several internal factors (Early-mover advantages, Price maintenance reserve, Recognition-seeking, Resilience gained through challenges and Choice of multiple blockchains) and external factors (Emergence of the cryptocurrency ecosystem, Regulatory constraints) that drive the success of stablecoin.