From Strunk & White’s Elements of Style: “Make definite assertions. Avoid tame, colorless, hesitating, noncommittal language. Use the word not as a means of denial or in antithesis, never as a means of evasion.”
Examples:
Instead of this . . . | Say this . . . |
He was not very often on time. | He usually came late. |
She did not think that alphabetizing the emails was a sensible way to use her time. | She thought that alphabetizing the emails |
Not all of the barrels had been inspected. | Some of the barrels had not been inspected. |
Not coming to work on time is a bad habit. | Coming to work late is a bad habit. |