You use their APIs in a way that commoditizes them. Ideally your customers don't care if you switch to Anthropic, because the LLM provider is not the reason customers are picking you. Likewise, there is some structural reason that OpenAI will never release a feature that rugpulls you, eg, no 'chat to your PDF'.

An extreme form is self-hosted on edge-only devices where folks are buying some other hw. Ex: Nvidia selling GPUs and giving out free Triton inferencing OSS software. But most are in the middle, eg, some accounting app now with LLMs. Our case of investigations in louie.ai is right at that boundary: OpenAI likes to support data analysis, but folks using Splunk/databricks/etc all day expect a lot more out of software here, and that's too at-odds with OpenAI's org chart and customerbase.