Probably because it's expensive, slow and adds more complications to their guardrails that humans need to check. It takes time and a lot of resources (human and

Probably because it's expensive, slow and adds more complications to their guardrails that humans need to check. It takes time and a lot of resources (human and compute) to make these big models. If the model is constantly being updated, how can you be sure it won't degrade in some unknown ways?