Carry out the instruction of the Load, don't let the Load grieve

I Samuel 15:1-16
The Load direct told Saul to totally destroy everything the belong to Amalekites, put to death men and women, children and infants, cattle and sheep, camels and donkeys.
Saul attacked the Amelekites all the way from Havilah to Shur,to the east of Egypt. But Saul and the army spared Agag and the best of the sheep and cattle , the fat calves and lambs- everything that was good.
Load said to Samuel:" I am grieved that I have made Saul king, because he has turned away from me and has not carried our my instructions.
When Saul met Samuel he didn't know he has sin, and he said to Samuel I have carried out the Load's instructions. Samuel told Saul:"Stop!, Let me tell you what the Load said to me last night"
Why?
Saul forgot this victory to Amalek is the war of the Load, it wasn't the honor of Saul, Saul has set up a monument in his own honor.
When one is proud then he forgot what God did on him.
The Load is grieved for He has made Saul king, Samuel cried out to the Load for mercy to Saul and Israel. He is an honest servant of the Load and the Priest of Israel, like Moses.
Samuel was troubled, it is means Samuel he had foresee the trouble.
The Load put the enemy of Israel to dead but let other tribe free, such as Kenites
How?
Follow the instruction of the Load, not only listen but also carry out the instruction totally, there is not any excuse. Even the mercy of our selves is not permitted for their will be good to us. This is the holy war, not one can touch anything in the holy war.