ChatGPT voice mode is a weaker model

ChatGPT's voice mode runs on an older, weaker model (GPT-4o era with a knowledge cutoff of April 2024) compared to other OpenAI products, even though talking to an AI might seem like it should use the smartest version. The article explains that OpenAI's highest-tier models perform much better on tasks like coding because those domains have clear, measurable success criteria (like whether unit tests pass) that make them easier to improve through reinforcement learning (training that rewards correct behaviors), and because business customers value these capabilities more.