Late last month, Moonshot AI released the weights for Kimi K3, a 2.8-trillion-parameter artificial intelligence (AI) model that only lags the very best models from OpenAI and Anthropic. Although released as an open-weight model with weights available for download, most consumers will not be able to experience its frontier capabilities. The author argues that amid hype around open-weight model announcements, model weights are only part of the story; without inference and test-time compute, it is impossible to serve users frontier AI, no matter how powerful the underlying model might be.