What is the purpose of Block 21 on a Sailor's performance evaluation?

Block 21 on a Sailor's performance evaluation is intended to record retention status. This block is critical because it directly aligns with the assessment of a Sailor's career progression, influencing future assignments and opportunities within the Navy. By documenting retention status, the evaluation provides leadership with a clear understanding of where the Sailor stands concerning their operational readiness and career development.

In contrast, the other blocks serve different purposes that do not pertain to retention status. For example, summarizing overall performance typically falls under other sections of the evaluation, while deployment history and listings of awards and achievements are addressed in their respective blocks. Each part of the performance evaluation serves a specific role in conveying a comprehensive picture of the Sailor’s contributions, but Block 21 distinctly focuses on retention, making it a vital element for personnel management.