Userbase and customer relationships are valuable. If someone else creates GPT5, but doesn't have a large user base, then OpenAI the company could buy that invention. Or, as we saw with deepseek in January, fast-follow with a comparable model within a reasonable amount of time.

Brands have value. If someone has logged into ChatGPT for two years daily, they have built a habit. That habit certainly can be disrupted, but there's a level of inertia and barrier -- something else has to be 10x better and not just 2x better.

When DeepSeek came out, I tried it out but didn't fundamentally switch my habit. OpenAI + Claude + Gemini instead caught up.