Occasionally, you want to own up to something without really taking the blame. You want to indicate that you know there’s a problem without indicating that you caused it. The passive voice can be very helpful.
Here’s the classic example: Mistakes were made.
You’re hoping that will come across as calm acceptance of the fact that something has — somehow! — gone wrong. In reality, it translates to “I made some mistakes but I’m a pompous twit and cannot admit to it. Furthermore, I think you’re such a dimwit that you won’t realize.” It’s like having your mom walk into the room where you stand alone, empty glass in hand and puddle at your feet, and say “Milk was spilt.”
There are times when the passive voice is the best option but that’s not when you’re trying to wriggle out of taking responsibility for something.
If you say mistakes were made, you’re making another one as you speak.
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