Sell the same product under two brands at the same time?
Optimal business strategy. Makes it look like there's more competition, and changes the decision from "do we use ChatGPT" to "Which GPT vendor do we use?"
Microsoft has a stake in OpenAI but they don't have a controlling interest in it. What they got instead was exclusive access to the models on Azure. So they benefit from OpenAIs success but they benefit more from their own success in the space and in a way they are competitors.
Optimal business strategy. Makes it look like there's more competition, and changes the decision from "do we use ChatGPT" to "Which GPT vendor do we use?"