The current thinking on emails – apart from the fact that they’re a necessary evil – is that they should be no longer than five sentences. Anything more than that, and you either need a meeting with the person, or you should walk down the passage and discuss the matter with them briefly.
People are so overwhelmed by their inboxes now, that they don’t even scroll down to read the whole email. So if the nub of what you have to say doesn’t appear in the first few sentences, as the email opens, chances are the rest won’t be read..
We’re not suggesting you religiously count your sentences, but it’s a good guideline. And it forces you to get straight to the point upfront and not spend unnecessary time waffling about the weather.
Remember, emails are a business tool, so be businesslike. Get to the point, get there fast, and if you can’t, perhaps email isn’t the best form of communication in this instance.