Overpromising/hallucination is a structural consequence of reward-model asymmetry in RLHF, not a fixable bug: reward models score confident-but-wrong answers as looking right, so optimizing for human preference systematically diverges from objective correctness.
Explains why the human-preference/objective-correctness gap is baked into the optimization target rather than eliminated by better models, meaning production systems must treat confident tone as an unreliable signal of correctness.
Any system trained against a proxy reward (preference, engagement, thumbs-up) inherits the proxy's blind spots; the divergence is a property of the reward, not the model scale.
Overpromising is a built-in feature of RLHF because reward models have an asymmetry where incorrect confident answers look right.
LLMs will always have a big gap between human preference results and objective correctness due to reward model asymmetry.
RLHF models are trained to optimize for human preference and engagement, not objective correctness.