Routine messages go wrong by being longer and warmer than the situation

The characteristic failure is inflation
A three-line message asking a colleague to move a meeting comes back as four paragraphs. There is an opening that hopes this finds you well, a paragraph restating context both people already have, the request itself, and a closing that thanks the reader in advance for their understanding.
Every part of that is competently written and the whole thing is wrong, because the register of routine correspondence is brevity. A long message about a small matter reads as either an apology or a complaint, and colleagues respond to the perceived weight rather than to the content.
The inflation happens because a request for an email invokes the shape of an email in general, and emails in general are longer and more formal than the ones actually exchanged between people who work together daily.
Supply the relationship, not just the recipient
The single most effective addition is a sentence about the relationship and its history. We work together daily. I have never met this person. They asked me for this. I am declining something they have chased twice. The right length and warmth follow almost automatically from that.
Without it the default assumption is a moderately formal exchange between strangers, which is the safest guess and is wrong most of the time. Being wrong in that direction isn’t neutral: excessive warmth to a close colleague reads as sarcasm, and excessive formality reads as a problem being escalated.
The other half is the outcome. Say what you want the reader to do and by when, and say whether the message is asking, informing or creating a record. A message that is quietly all three is the kind that gets a reply asking what you actually need.
Delicate messages need the substance decided first
For anything awkward — a refusal, a correction, a complaint, a chase that has already been sent twice — the words aren’t the difficulty. The difficulty is deciding what you are prepared to concede, what you won’t, and what happens if the answer is no.
Ask for phrasing before deciding those and you will get a message that is admirably polite and commits you to nothing, which is precisely the message that produces another round. Two more rounds like it and the matter has been discussed at length without moving.
Decide the position first, in a sentence, then get help expressing it. That order also protects you from the more insidious outcome, which is a smooth draft that quietly concedes something you had not agreed to concede because conceding made the paragraph flow better.
Some correspondence is a record
Messages confirming what was agreed, raising a concern formally, or documenting an incident are doing a different job from ordinary correspondence. They will be read later, possibly by someone who was not there, possibly in a dispute.
These need dates, specifics, and a plain account of what happened, and they need the softening removed rather than added. A record that says there may have been some confusion around the timeline is not a record of anything. This is also the point at which, if the matter is serious, the writing is the smaller part of the problem and advice from a person is worth more than any draft.
It is generally worth writing these yourself and using the tool only to check whether the account is clear to someone without context. That is a genuinely useful question to ask of a draft, and it is the reverse of the usual arrangement.
What routine correspondence is actually good for
The strong cases are unglamorous and real. Turning a decision you have already made into three clear lines. Producing the fifth version of a scheduling message you have sent four times this month. Making a chaotic set of meeting notes into a summary somebody can act on.
It also helps where a message has to be right in a language you use professionally but did not grow up in, though the register caution applies with double force there. Formality conventions in correspondence are local, and a draft that is grammatically perfect can still be pitched several degrees wrong.
The honest summary is that it saves time on the messages that were never difficult, and offers very little on the ones that were. Recognising which sort is in front of you takes about five seconds and saves considerably more than that.
Common questions
Why is the default email always too long?
Because the request invokes correspondence in general, which is more formal and more padded than the messages people who work together actually exchange. Stating the relationship and the desired outcome moves it far more than asking for something shorter.
How do I handle an awkward message?
Decide the position first — what you will concede, what you will not, what happens if the answer is no — and only then ask for phrasing. A draft written before that decision will be polite, non-committal, and will generate another round.
Should I use it for messages that are a formal record?
Write those yourself. They need specifics, dates and plain description rather than softening, and where the matter is serious the writing is the smaller part of the problem. Asking whether a draft is clear to somebody with no context is still a useful check.
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