Dogs commonly play with balls, and there seems to be something about the size, shape, and movement of a ball that fits very well with how many dogs naturally engage with objects. Balls roll, bounce, and are easy to hold in the mouth.

This allows a ball to be incorporated into a direct and uncomplicated game of fetch as the individual throws the ball and the dog retrieves the ball. Some dogs are more consistent returning the ball than others, but many will chase the ball regardless of what happens afterward.

Some dogs prefer to play with tennis balls, while others go for rubber ones or textured plastic balls.

The type of material changes how far a ball bounces and how it feels when carried or chewed. If the ball is too large, the dog might struggle to handle it and a ball that is too small might pose a choking hazard. Some dogs quickly chew through softer balls, therefore it may be necessary to select something more durable.

The movement may also be part of the appeal.

When a ball rolls away or bounces erratically, that movement may hold the dog's attention more than a non moving object.

Dogs with strong herding or hunting instincts are often attracted to this movement, however in general all dogs may appreciate a moving ball.