This is often done to prevent the opponent from entering.

He believed in holding back and preventing the opponent from attacking.

The evil characters do not have a chance to win the game (though they can prevent the opponent from winning).

He stirs himself only to prevent the opponent from getting the upper hand.

Furthermore, certain types of cards, when played, prevent the opponent from playing an identical card.

Strategically, the offense can prolong their possession of the ball to prevent the opponent from scoring.

To prevent the opponent from escaping the back mount, it needs to be stabilized.

They allow a player to inflict high damage with little effort, and prevent the opponent from getting into a good footing to attack.

When a player surrounds an intersection with his stones, this prevents the opponent from taking certain key pieces.

This is done to prevent the opponent from escaping the hold, and to be able to apply additional pressure by extending the hips.