Playing actively is an important part of good chess strategy. If you play nothing moves, expect to lose. You need to play actively in order to win.
Playing actively means getting your pieces and pawns out, trying to control more space, and trying to attack. If you play actively, there is a much higher chance that you will get an attack, and have a successful attack.
Active play is also important in defence. If you are attacked, active defence is more likely to succeed than sitting back passively and waiting for the final checkmate.
Related Chess Tactics
Read more about these related chess strategies: