When recording a substitution, what should NOT be done according to the established procedure?

When recording a substitution in volleyball, it is vital to follow the established procedures to ensure accuracy and clarity in the match records. The answer indicates that leaving the outgoing number unmarked should not be done, and this holds true for a few reasons.

Leaving the outgoing number unmarked can lead to confusion and inaccuracies in tracking player participation and match statistics. Properly slashing the outgoing number is essential because it visually indicates that the player is no longer participating in the match. This creates a clear record of who is currently on the court and who has been substituted, which is crucial for keeping accurate game statistics and for managers, coaches, and referees to understand player changes.

In the context of the other options, slashing the outgoing number and marking the team's substitution history ensures that everyone involved in the match is on the same page. Recording the team score at the time of substitution is also crucial as it provides context for when the substitution occurred. Therefore, not marking the outgoing number disrupts the flow of this precise record-keeping process.