decontextualised

They make little sense without being able to see the roadworks out of shot to the right. Just out of shot to the right is a large metal fence-thing behind which is a dirty great big hole whose walls are stuffed with the ends of sewage-pipes. The hole gives the cones context and explains their presence. If the hole and fence was filled and removed suddenly and without explanation it would give the impression that the cones were unnecessary. In the proper context the cones are entirely necessary and justified. Unfortunately someone might come along too late to see the hole, see the cones without the hole and the fence and consider them out of place. Still, the person who dug the hole knows exactly why the cones are there.

***

Letting something slip out in verbal communication is one thing; the average person must walk past several conversations a day in which it's evident that at least one of the participants are speaking faster than their brain can edit.
Written communication is thoroughly different. Most people type more slowly than they can speak so they have more time to plan ahead and look ahead linguistically as well as in their subject. Previous utterances need not be remembered as they are written down to be checked and reviewed and spellchecked and reconsidered and reworded. Finally, the issue or publication or sending of the finished writing is only performed with a deliberate button-press (or envelope-seal, stamp-lick and letter-post) which provides further opportunity to review and revise and rethink. By the time the writing gets to posting (or Posting) stage it deserves to have been sufficiently thoroughly examined to represent both what you truly think and what you're certain you want to indicate to anyone who reads it that is represents what you think. If it doesn't or if you aren't, don't.