LLM Abstention Can Be a Prompt Artifact, in Addition to Genuine Uncertainty

Understand

Large Language Models (LLMs) are increasingly trained to abstain from answering questions they are unsure about.

• However, this ability is often misused: in real-world applications, user prompts sometimes contain uncertainty elements, and driven by this, LLMs are inclined to abstain even on problems they are capable of solving.
• We argue that LLM abstention is not only an expression of genuine uncertainty; it is also an artifact that can be largely influenced by prompts.
• We name this phenomenon *Abstention Inflation*.