Samuel said to Saul, You have done foolishly; you have not kept the commandment of Yahweh your God, which he commanded you: for now would Yahweh have established your kingdom on Israel forever.
Samuel’s departure from the battlefield (1 Samuel 13:15) was symbolic of the breach that now opened up between Samuel and Saul. Saul’s presumptuous plan also failed to bring his departing soldiers back to him.