Why is detecting AI-generated text so difficult?

Human language is incredibly fickle and complex — one of the main reasons AI-generated text is so tricky to detect.

Bamshad Mobasher, IEEE member and chair of the AI program at DePaul University elaborates that “text is what these models are trained on. So, it’s easier for them to mimic human conversations.”

“Detection tools look for patterns — repetitive phrases, grammatical structures that are too regular, things like that,” Mobasher said. “Sometimes, it’s easier for a human to spot, like when the text is ‘too perfect,’ but to be certain it’s AI-generated is challenging.”

Unlike image generators, which can produce telltale signs like extra fingers or distorted facial features, Mobasher explained LLMs rely on statistical probabilities to generate text — making their output feel more seamless. As a result, spotting errors in AI-generated text — like nuanced phrasing or subtle grammatical irregularities — is far more challenging for both detectors and human readers.

This is what makes AI-generated text so dangerous as well. Mobasher warns that “it becomes easier to produce and generate misinformation at scale.” With LLMs generating fluent, polished text that can mimic authoritative voices, it becomes much harder for the average person to discern between fact and fiction.

“With AI, it’s actually much easier to launch these attacks,” says Yang. “You can make the email very fluent, conveying the message you want, and even include personalized information about the target’s role or mission at a company.”

On top of its potential misuse, AI-generated text makes for a shittier internet. LLMs from companies like OpenAI and Anthropic scrape publicly available data to train their models. Then, the AI-generated articles that result from this process are published online, only to be scraped again in an endless loop.

This cycle of recycling content lowers the overall quality of information on the web, creating a feedback loop of increasingly generic, regurgitated material that makes it difficult to find authentic, well-written content.

There’s not much we can do about the lightning-fast acceleration of AI and its detrimental effects of internet content, but you can, at the very least, tap into your knowledge pool of media literacy to help you discern what’s human-made and what’s generated from a bot.

“If you see an article or report, don’t just blindly believe it — look for corroborating sources, especially if something seems off,” Yang says.