Your writing will be more successful if you focus on positive wording and a positive tone rather than negative. This focus is more likely to produce the response you want, be more persuasive, and generate goodwill. In contrast, negative words may generate resistance.
Negative example: You are 2,000 points short of the requirement for an upgrade.
Positive example: You only need 2,000 points to qualify for an upgrade.
You will appear more confident and assertive by stating what something is and what you can do, rather than what something is not or what you cannot do.
Negative example: I cannot process your enrollment without the proper form.
Positive example: I will process your enrollment when I receive the proper form.
You will naturally write either positively or negatively. I tend to write negatively, so if you are like me, take a few minutes to change your negative statements to positive ones and improve your writing and the response you get.
Excerpt from my workshop Writing for the Workplace. Business Writing for Results.