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Why does AI lie? Hallucinations explained simply

Rohini Gaonkar on May 08, 2026

In the previous post, I showed you an AI doing something genuinely useful, helping me adapt a recipe for a dinner party. We talked about the basic ...
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Ingo Steinke, web developer

Thanks for the practical explanations! A few further thoughts:

  • AI will ignore sources, even a short PDF you just uploaded, and prefer its lazy guesswork vs. AI is so good at processing and summarizing large amounts of text = depends on which model?
  • AI isn't always sycophantic. Sometimes it stubbornly insists on some made up claim to prevent obvious self-contraction.
  • Guardrails add cautionary subjunctive, "sometimes" and "often" everywhere. Ask AI to elborate and sustain claims using recent and authoriative sources, where it matters!
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GoDavaii - Advanced Health AI

The challenge of hallucination you highlight is exacerbated in voice-first interfaces. When a user asks 'mujhe bukhar hai' (I have a fever) in their mother tongue, they need accuracy, not plausible invention. There are no visual cues to flag uncertainty in a spoken response.

This makes data provenance and confidence scoring even more critical.

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Rohini Gaonkar AWS

I focused mostly on text-based AI hallucinations, but you opened up my mental model further. You are right, voice makes it trickier because users lose visual trust signals and confidence can be mistaken for correctness.

The multilingual example makes this even more real. Provenance + confidence scoring feels critical in these use cases. Do you think voice assistants should say “I’m not certain” or “this information comes from medical guidelines” instead of optimizing purely for smooth conversational flow in the future? Or something else?

Thanks for sharing this perspective!

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Ken W Alger

This is a great primer on the 'why' behind hallucinations. Most people assume AI is a database when it’s actually a reasoning engine—and those two things have very different relationship statuses with the 'Truth.'

However, from an Infrastructure Thinking perspective, the goal isn't just to understand why it lies, but to build a system where those lies can't reach the end-user. I’ve been working on a pattern I call the Sovereign Gateway, which treats the LLM as an untrusted agent. Instead of just hoping the model doesn't hallucinate, we use Versioned Snapshots and Forensic Integrity Checks to validate the output against a 'Ground Truth' database—like the SQL transactions and procedures mentioned in other foundational stacks—before the data is ever surfaced.

In my Sovereign Synapse series, I argue that the 'Staleness vs. Latency' trade-off is often where these hallucinations hide. If the data pipeline is too slow, the agent 'fills in the gaps.' By moving toward Shadow-Routing logic, we can audit the agent's forensic integrity in real time.

The 'Why' is important, but for those of us building production-grade AI, the 'How do we contain it' is the real challenge.

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Rohini Gaonkar AWS

Thank you for the details Ken. The how is definitely a bigger challenge for production grade systems. The evaluations and ground truth are now so much more important! I would love to read more on your patternm, can you please point me to the right links?

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AudioProducer.ai

The "context reduces, doesn't eliminate" framing carries over neatly to AI markup on long manuscripts. We run an auto-assign pass that tags every line in a chapter by speaker — narrator vs. each character — and even with the full chapter in context, the model will occasionally invent a speaker that the prose doesn't actually attribute, especially in dialogue blocks where the author drops attribution between turns and the reader is left to infer who's talking. Same prediction-filling-a-gap mechanism you describe, just applied to character attribution instead of facts. What we've found works is treating the pass as a draft that the writer expects to correct, rather than a finished answer — close in shape to your grounding + evaluation + guardrails triple, with the human edit step acting as the evaluator. The model is great at producing a useful-looking attribution; the writer is the one who knows whether it's actually true.

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Esin Saribudak

A recent response I got from a model when I asked where it got some numbers -- "I'm gonna be honest, I made that up." 😂

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Joske Vermeulen

Recognisable 😂

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Rohini Gaonkar AWS

🤣 atleast model is honest!

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Joske Vermeulen

Just yesterday I had Opus asking me after every prompt: we have been going for a long time, let me save my context and continue tomorrow 😂

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Rohini Gaonkar AWS

lol "do what you have to do buddy"

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Joske Vermeulen

:D I really answered every time, you are a computer, just continue. But it became even worse, so I needed to start a new session :)

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Rohini Gaonkar AWS

yes! I am talking about how long context window degrades the quality in upcoming blogs!

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Joseph Boone

Interesting, kind of seems like some big corps are getting in on the "fake AI generated junk".

As far as I'm aware though there are a lot awesome options to learn, plan, and progress using AIs.

  • Anthropic
  • OpenAI
  • Grok Code Fast
  • Gemini & Gemma
  • Copilot is also highly underrated as a built-in Windows AI in general

OPs point stands though, never believe the AI unless you are confident and back check frequently.