What is the primary focus of a successful ball toss according to the checklist?

The primary focus of a successful ball toss is executing one solid upward movement. This is crucial because a clean and efficient upward motion helps to establish proper mechanics and control during the toss, which sets the stage for a smooth jump ball. A consistent upward movement ensures that the ball is released at the optimal height and with the right amount of force, allowing both players involved in the toss to have a fair opportunity to gain possession. This aspect of focus is vital because it contributes to the overall fairness and effectiveness of the jump ball, showcasing the skills of the referee while maintaining the flow of the game.

Other aspects, such as timing or the use of one hand, may contribute to the procedure but are not as fundamental as the quality of the upward movement. Multiple players being involved is not relevant to the toss itself, as the focus is on the referee's actions during this critical moment of the game.