Why did government of kerensky fail?

The Provisional Government (PG) lost legitimacy with the Russian people because it failed to remedy the problems that led to the overthrow of the Tsarist regime in the first place: an end to World War 1, more food and manufactured good and a redistribution of land to the peasant farmers.

This was mainly because the PG was composed of ministers who were more dedicated to retaining the basic social structure of Russia except for the abolition of the autocratic Tsarist rule in favor of a democratic constitutional rule. The Russian people wanted an end to Russia's involvement in World War 1, but the PG continued the war to protect its own interests. The Russian people wanted an end to shortages of food and manufactured goods, but the PG was unable to do that. The Russian people wanted a redistribution of land from its owners to the peasant farmers that worked it, but the PG wouldn't do that until the planned Constituent Assembly was convened.

From the time the PG took control after the February 1917 revolution until the October 1917 Bolshevik Revolution, the Bolshevik Party agitated against the PG among soldiers, workers and peasants to the point where the Bolshevik Party was seen more and more as the only party who would honor the ideals of the February Revolution. The PG was simply more of the Tsarist regime, except that it was run by several ministers instead of one Tsar.