Why would those who started the French Revolution and created the famous "The declaration of rights of man and of the citizen", say the revolution was not successful?

The French Revolution was inspired by and spread lofty ideals of human equality, of liberty, of human rights and people's sovereignty. Those were beautiful, noble ideas that have largely shaped the democratic present of Western nations or of any nation living in democracy. But this is the long run, 230 years after they were proclaimed formally.

In the short run, the revolution was a great political and social experiment that failed to meet their high goals in the immediate years following the seizure of La Bastille. Revolutionary terror, instability, enormous human suffering and tragedies, and war occurred during the revolutionary years. Chaos came to an end in France only when a powerful and ambitious man, Napoleon Bonaparte, restored autocratic rule and crowned himself emperor. Another tyranny put an end to the Revolution. That's why the revolutionary leaders could not say they were succesful in the short run.