It depends on your ideology. If you are a supporter of communism, it was not a failure at all. It bolstered Mao's claim that the Chinese Communist Party was the champion of the common people and brought him great prestige among the majority of Chinese peasants. If you do not support communism, the Long March could be seen as a failure for China since it strengthened the Chinese Communist Party and allowed it to survive the onslaught of the KMT.
