Authenticity is a behaviour, not a tone of voice

Every brand guideline written since 2018 contains the word authentic. Almost none of them explain what a writer is supposed to do with it.

Here is the uncomfortable part: authenticity is not a register you can adopt. It is the gap between what an organisation says and what it does, and copy cannot close that gap — it can only make it more visible. A company that treats its people badly and publishes warm copy about its culture has not been inauthentic in its writing. It has been inauthentic, and the writing found it out.

What copy can do is stop making the gap worse. That means claiming only what is true, naming the trade-offs rather than smoothing them, and resisting the urge to describe an ambition in the present tense. "We are working towards" is a stronger sentence than "we are", when the second one is not yet true.

You cannot write your way into being trusted. You can absolutely write your way out of it.