Name: Towards AI Legal Name: Towards AI, Inc. Description: Towards AI is the world's leading artificial intelligence (AI) and technology publication. Read by thought-leaders and decision-makers around the world. Phone Number: +1-650-246-9381 Email: pub@towardsai.net
228 Park Avenue South New York, NY 10003 United States
Website: Publisher: https://towardsai.net/#publisher Diversity Policy: https://towardsai.net/about Ethics Policy: https://towardsai.net/about Masthead: https://towardsai.net/about
Name: Towards AI Legal Name: Towards AI, Inc. Description: Towards AI is the world's leading artificial intelligence (AI) and technology publication. Founders: Roberto Iriondo, , Job Title: Co-founder and Advisor Works for: Towards AI, Inc. Follow Roberto: X, LinkedIn, GitHub, Google Scholar, Towards AI Profile, Medium, ML@CMU, FreeCodeCamp, Crunchbase, Bloomberg, Roberto Iriondo, Generative AI Lab, Generative AI Lab VeloxTrend Ultrarix Capital Partners Denis Piffaretti, Job Title: Co-founder Works for: Towards AI, Inc. Louie Peters, Job Title: Co-founder Works for: Towards AI, Inc. Louis-François Bouchard, Job Title: Co-founder Works for: Towards AI, Inc. Cover:
Towards AI Cover
Logo:
Towards AI Logo
Areas Served: Worldwide Alternate Name: Towards AI, Inc. Alternate Name: Towards AI Co. Alternate Name: towards ai Alternate Name: towardsai Alternate Name: towards.ai Alternate Name: tai Alternate Name: toward ai Alternate Name: toward.ai Alternate Name: Towards AI, Inc. Alternate Name: towardsai.net Alternate Name: pub.towardsai.net
5 stars – based on 497 reviews

Frequently Used, Contextual References

TODO: Remember to copy unique IDs whenever it needs used. i.e., URL: 304b2e42315e

Resources

Free: 6-day Agentic AI Engineering Email Guide.
Learnings from Towards AI's hands-on work with real clients.
Nobody Taught LLMs to Say “I Don’t Know”
Latest   Machine Learning

Nobody Taught LLMs to Say “I Don’t Know”

Last Updated on August 19, 2026 by Editorial Team

Author(s): The Dev Loop

Originally published on Towards AI.

Hallucination is a grading problem.

Contrary to popular belief, the chatbot on your screen does not invent facts because something inside it is broken. It invents facts because we grade it, and the grading rewards a confident guess over an honest shrug.

Nobody Taught LLMs to Say “I Don’t Know”

Photo by Nguyen Dang Hoang Nhu on Unsplash

The article argues that LLMs don’t “hallucinate” due to some internal malfunction; they are trained and evaluated with grading rubrics that treat confident guessing and honest abstention identically, so bluffing becomes rational under the scoring rules. It explains the underlying next-token prediction mechanism, then uses benchmark-style examples (including comparisons of models with different tendencies to guess vs. abstain) to show how accuracy-focused leaderboards incentivize confident falsehoods. The author connects this to both automated benchmark design and later human preference tuning that implicitly rewards sounding sure, discusses limits like pretraining data coverage and calibration, and critiques the branding of “hallucination” as mystery that obscures responsibility. Finally, it proposes the fix: change the mainstream scoring/rubrics (not just add more tests) so that only sufficiently confident answers score, while “I don’t know” is penalized differently—shifting the incentive so models learn to stop instead of bluffing.

Read the full blog for free on Medium.

Join thousands of data leaders on the AI newsletter. Join over 80,000 subscribers and keep up to date with the latest developments in AI. From research to projects and ideas. If you are building an AI startup, an AI-related product, or a service, we invite you to consider becoming a sponsor.

Published via Towards AI


Towards AI Academy

We Build Enterprise-Grade AI. We'll Teach You to Master It Too.

15 engineers. 100,000+ students. Towards AI Academy teaches what actually survives production.

Start free — no commitment:

6-Day Agentic AI Engineering Email Guide — one practical lesson per day

Agents Architecture Cheatsheet — 3 years of architecture decisions in 6 pages

Our courses:

AI Engineering Certification — 90+ lessons from project selection to deployed product. The most comprehensive practical LLM course out there.

Agent Engineering Course — Hands on with production agent architectures, memory, routing, and eval frameworks — built from real enterprise engagements.

AI for Work — Understand, evaluate, and apply AI for complex work tasks.

Note: Article content contains the views of the contributing authors and not Towards AI.