An internal persuasive message should explain why your idea or policy is the best option. this is known as the

An internal persuasive message should explain why your idea or policy is the best option. this is known as the Rationale.

There are many components of internal and external persuasive messages in which they differ from each other. like in Rationale, in internal persuasive message it is elaboration about why your idea or policy is the best option but in external persuasive message it is elaboration about how your product or service benefits customer.