FAILED MISSION?

Lord Krishna stayed at the house of Vidura when he came for the peace mission to Hastinapura.
Vidura who was like a father figure, was concerned about the  Kauravas offending the Lord. So he suggested that Krishna  not speak with the Kurus, specially with Duryodhana, and gave many reasons.

Vidura said, “Duryodhana has given up dharma and artha, he is full of anger, destroys honor of others and is infatuated by honor for himself.  He has rejected the good advice given by elders, he is attached to sensuality, his intelligence is not steady.He follows the  path of his desires, he will not listen to you, Krishna. He has no plan of truce.  He believes more in the power of his followers. He thinks Karna alone is sufficient to destroy the Pandavas. He and his brothers have no desire for peace, and you my lord are trying for peace. He suspects you too, therefore whatever good you say, he will not listen to you. They are convinced, that even Indra cannot defeat them. All those who fear you have joined the Kurus, and are ready to die for the cause of the Pandavas destruction.  I am very much concerned about you. I am very confident about your influence, power of action and intelligence, but out of love, respect and friendship, I am speaking these things.”

Lord Krishna replied “ what you say is truthful, timely, and full of wisdom.  But still hear why I am here at Hastinapura.” Krishna continued, “I am very much aware of Duryodhana's  vile behavior, mother Bhumi is ready to see the destruction of the host of armies, along with the horses, and elephants.
I am trying to avert this war.Human beings should put all efforts to do that which is dharmik. Even if he fails in the work of dharma, still it is glorious.I understand that all these kings are fighting because they are confident of Duryodhana and Karna and that  they will give them victory.  I know for certain that the root of evil is in the party of the Kaurvas.
One who is suffering because of habit should be helped , if one does not help then, he is cruel and hard hearted, this is the opinion of the learned. One more thing, those who are sinful fools and who think me as their enemy should not accuse me of not trying my best to stop this war.With all this if Duryodhana still does not listen to me then it is his great ill fortune. My only intention is to benefit both the parties.”

A mission can only be successful, when the other party is also willing to change.
Lord in this world, can give us all the facilities to change. He can give good advice, work really hard in that direction, but ultimately it is up to every one to make the choice. God directs, but does not dictate since we have the independence to decide.

Yes certainly Krishna failed, but failed in trying, this is the glory of God.
The living entities independence is the key factor in making  the decision in favor of benefiting oneself or harming oneself.