Regardless of its length, a business message should have only one purpose. This means we do not want to split our purpose among different sentences. Here is an example of an unfocused purpose:
This document describes the protocol for Procedure X. It also ensure operational safety and efficiency.The writer seems to believe the messages has a dual purpose, to describe a protocol and to achieve two operational benefits. But the benefits are actually the result of following the protocol. The purpose would have been more focused if he had written one of these sentences:
This protocol for Procedure X ensures operational safety and efficiency.
To ensure operational safety and efficiency, follow this protocol for Procedure X.
Follow this protocol for Procedure X to ensure operational safety and efficiency.Building on the previous WORDS ON THE LINE post, the idea is start the message with the purpose, and to assert it in one sentence.