Some approach chess with an extremely defensive mentality. This works in some situations and not in others. Being too defensive leads to your primary pieces being stuck on the back row and being of little offensive value. This is particularly true when your queen, bishops, and rooks are trapped behind the line of pawns. To win a game of chess you need to develop your back row pieces at some point. A plan of how you are going to develop them will offer you a strong advantage.
Think of your primary chess pieces as sleeping soundly in the comfort of the barracks before the war begins. If those most powerful soldiers remain there, they cannot thwart your enemy during the war. Develop these primary pieces in the manner that the game progresses. Typically this means that bishops move from the back row quickly followed by knights, the queen, and finally the rooks. The rooks typically move out when the middle game is starting, or the midpoint of the match.
Too often inexperienced chess players do not get their primary pieces off of the back row soon enough and those pieces are rendered ineffective. A worse scenario is that they are trapped on the back row and left rather defenseless. Think of the rook being in its opening position with a knight beside it. If the pawn in front of the knight has moved forward your opponent's bishop easily, and freely takes that rook through the semi open file. Allow the powerful pieces from your back row to work for you, not against you. Allow them to be offensive as well as defensive and you will have moved towards achieving that all-important balance in your chess game.