Why AI Writing Is Quietly Eroding Your Professional Credibility

When a manager sends an email that reads as AI-generated, two things happen. The recipient notices, even if they can’t say why. And from then on, every email from that manager gets read through a different filter.

This is the asymmetric problem of AI writing in professional life. Getting flagged as the person who sends machine-written messages is not a one-time cost. It accumulates. It compounds. And it’s almost invisible to the person paying it.

Last month, Leadership IQ launched a free AI writing detector. People immediately started pasting in their own work. Emails to their bosses. Performance reviews. Policy memos. Cold outreach. LinkedIn drafts. The kind of writing that fills a normal workweek for any executive.

The submissions added up to a real sample of workplace writing, with each sentence scored as AI-generated, human, or somewhere in between. The patterns that came out were not what most leaders would predict.

The Vocabulary Problem Is The Smallest Part Of The Problem

Most discussions of AI writing focus on giveaway words. “Delve” and “leverage” and “tapestry” have become punchlines online, and entire blog posts now exist to enumerate the buzzwords ChatGPT overuses. Those words do appear in AI-flagged writing. But they account for a small fraction of why a paragraph reads as machine-generated.

The dominant tells are structural, and they show up in writing that contains zero suspicious vocabulary.

So what’s the biggest tell? The new report, How to Get AI to Write Like a Human, shows it’s sentence length variation. In writing flagged as human-generated, more than a quarter of sentences were five words or shorter. In AI-flagged writing, fewer than four percent were that short. Humans use fragments. They write “Thoughts?” and “Happy Friday.” and “Not sure yet.” AI almost never does. On the other end, AI-flagged writing concentrated about 40 percent of its sentences in the 21-to-35-word range, compared with roughly 13 percent of human writing. The technical name for this is burstiness, and human writing has it in abundance. AI cruises at a steady, professional pace and rarely breaks rhythm. That even pace is the giveaway.

The second pattern is the absence of emotional punctuation. Across thousands of sentences of AI-flagged writing in the analysis, exclamation points appeared zero times. Question marks appeared roughly fourteen times more often in human writing than in AI writing. Parentheses (the kind humans use for asides and qualifications) appeared nearly three times more often in human writing. AI uses punctuation to organize ideas. Humans use it to express how they feel about ideas. A draft full of commas but no exclamations, no questions, and no parenthetical asides will read as machine-generated even when every word is correct.

There’s a third pattern that’s even more counterintuitive: the opening word of the sentence. Sentences that begin with “It,” “These,” “In,” and “This” were dramatically over-represented in AI writing. Sentences that begin with “So,” “Let,” “Hi,” “See,” “You,” and “I” dominated human writing. Human writers opened sentences with “I” more than twice as often as AI writers did. The first-person voice was nearly absent from machine-generated text. AI defaults to a disembodied perspective where findings emerge and considerations apply, but no specific person is doing anything.

Why The Cost Of AI Writing Is Asymmetric

So why is this a leadership problem and not a writing problem? The first time a colleague suspects an email is AI-generated, the cost is small. The second time, an impression starts to form. By the fifth or sixth time, the colleague is reading every message from that person through a filter, and the filter quietly degrades the credibility of even the messages the person wrote themselves.

It’s the same mechanism that makes a single news outlet’s editorial bias contaminate a reader’s view of its straight reporting. Once the impression forms, it doesn’t sort.; it just colors everything.

And the leader paying this cost rarely knows they’re paying it. No one writes back to say, “By the way, this email sounded like ChatGPT.” The recipient just makes a note, recalibrates, and moves on. The behavior continues, the impression deepens, and bit by bit, the leader’s communications lose credibility.

What Actually Fixes AI Writing

So what should leaders do? The instinct, once aware of the problem, is to scan for vocabulary. Find the “delve.” Replace the “leverage.” Strip out the “robust.” This handles the surface but not the structure. A paragraph can be free of every suspicious word and still sound like AI because the sentence rhythm is wrong, the punctuation is sterile, and every sentence opens with an abstract pronoun.

The real fix is structural. Vary sentence length, including the willingness to write fragments. Use punctuation to express emotion. Open more sentences with “I” and “We” and conversational connectors. Let the small imperfections of natural writing remain on the page.

Curious how your own writing stacks up against these patterns? You can paste a writing sample into any major AI writing detector (or use the free Leadership IQ AI writing detector mentioned above). Most people are surprised by what they see. Writing they were certain sounded like them comes back flagged. Writing they thought an AI helped with sometimes passes clean. The patterns that give AI away are not the ones most professionals expect.

The deeper point for leaders is that AI is not going to become less useful for drafting. It’s going to become more useful, more invisible, and more woven into daily work. So the question is not whether to use it. The question is whether what arrives under your name still reads as your voice.

The credibility cost of getting that wrong is paid quietly, across every communication, by the person who can least afford it.

Mark Murphy is a New York Times bestselling author, keynote speaker, and founder of Leadership IQ, where his research-driven executive coaching helps leaders close the gap between feedback and real behavioral change.

Source: Forbes.com