In reading the chapter I found that the Israelites had the Ark of God (symbolic to the Presence of God) when they went for battle, but they still lost the battle. The Presence of God was there, then why did they lose the battle. I guess, the Israelites were trying to work out a formula instead of a relationship by taking the Ark with them. They remember God's power to their people in the olden times.
Its not that God's Presence was not powerful, God would never give His power to people who want to use it for their own gains and still live in disobedience.
Firstly-They did not seek God to know whether this was God's will for them or not. Its about seeking God's will.
Secondly-Following a religion-not the relationship. They did what the Israelites had usually done in the past when they went out to battle, the Ark was with them. Its about the relationship.
We do that many times, seeking for God's Presence for things He wouldn't even have us do. Let's seek God for His plans for our lives. We'll find success in our seeking Him only then.
Also, lets not seek God's presence for the fancy of it, for the show of it, but His Presence to dwell in it. To enjoy God's Presence and know God more and increase our Love for Him.
Conclusion:-The Presence is not sought so we can be successful in our plans but so that we can have fellowship with God and that God may make us successful in His masterplan for our lives.