Professionally Yours
Sloppy letters give the sender a cheap, unprofessional image. I don't want letters making an impression I'm not proud of, so I don't send them if they're "almost OK."
As a dictator (of letters, thank you), I'm always fighting wordiness. Many of the poor letters I receive are dictated and not read. If you dictate, you or your secretary should make an effort to cut unnecessary words that creep into the recorder. If for some reason you can't read it before mailing, say so in the letter so the reader will better understand any imperfections.
Many people are wordy. Where did "enclosed please find" and similar trash come from? Write like you talk. Unnecessary words distract from your message.
An excellent quality check is simply to look at what you've written and take out the extra words. A letter with 20 words in two sentences is far more effective than saying the same thing in 40 or 60 words. Words are precious. Use them sparingly.
I often find myself deciding whether to send a typewritten letter, a handwritten note, or use the telephone. Most of the time I make my decision based on whether or not a written record is desirable. If so, it's typewritten. If not, I choose telephone or handwritten note, depending on the degree of formality. A note of caution–I've found myself writing personal notes too quickly, only to later discover I didn't convey the thoughts I intended. Proofread your handwritten notes, too.