Let's set the context of the story. King Saul disobeys God. God had said for Saul to wipe everything out in a neighboring nation. However, Saul keeps the king alive and some choice selections from the livestock. When asked by Samuel why he didn't obey Saul answered that he had in fact obeyed. Not only did he just obey, he did better than obey. He kept all these great animals to sacrifice to the Lord.
The verse I quoted is God's reply through the prophet Samuel. How often do we disobey when we think we are obeying? How often do we dishonor the name of the Lord and we excuse it because we had "good intentions." People hate the church because the church is full of people who "have good intentions" and yet are so Christ-less in their lives at the same time. People hate the church and yet love Jesus. How can that be? It can be because we are falling into the trap of Saul. The Christian life is not difficult to understand. Jesus summed up all of the OT Law in two commands: Love God and love others. How often do we fail in one of these two areas all the while "having good intentions?"
Obedience is better than sacrifice! Just obey! Be like Jesus! Imagine how different the world would be today if the church were filled with Jesus followers instead of Christians!