What is a common characteristic of Non-Directive Publications?

Non-Directive Publications are designed to offer suggestions and guidance rather than impose mandatory requirements. This flexibility allows users to adapt and modify the recommendations based on specific circumstances or preferences without violating any regulations. The key characteristic is their advisory nature, encouraging personnel to use discretion and judgment in applying the guidance, rather than following rigid rules. This contrasts with directives and instructions, which typically include enforceable regulations that must be adhered to, emphasizing the intended use of Non-Directive Publications as helpful frameworks rather than prescriptive mandates.