ฺBy this reckoning, the CCP's key accomplishment was to find the means to sustain itself as the only viable alternative to GMD rule. But in the final analysis, the GMD collapsed on the mainland primarily of its own dead weight Indeed, starting in mid-1949 one of the CCP's main problems become the speed of the retreat of the GMD forces. Those in south China often fled so rapidly that the CCP military had difficulty keeping up, and the bandit gangs that took over in the interregnum roved nettlesome for the communist forces when they arrived.