Liquid launch vehicles, as the primary means for human space access currently and in the foreseeable future, have their testing and launch modes closely tied to the technical status of the launch vehicle, the construction of launch site conditions, and the achievement of high-efficiency launch capability. Through a comprehensive analysis of the main characteristics and underlying reasons at each developmental stage of global liquid launch vehicle test-and-launch modes, the evolution of these modes is divided into three phases: reliability-and-safety-driven, test-efficiency-driven, and flexibility-and-cost-driven. In each phase, the test-and-launch mode of liquid rockets is refined and improved based on the previous stage, with current developments emphasizing safety, reliability, efficiency, and low cost simultaneously. The key factors influencing the selection of test-and-launch modes for liquid launch vehicles are analyzed, including technical feasibility and heritage, launch-site adaptability, test-and-launch efficiency and flexibility, and economic considerations. Major trends in the future development of test-and-launch modes are proposed, providing useful references for the construction of future space launch sites.