If you want to try the o1 models for yourself, you can create a free ChatGPT account, sign in, toggle "alpha modes" from the model picker, and choose o1-mini. If you want to try o1-preview, you'll have to subscribe to a ChatGPT Plus account for $20 per month.

The gist is that perhaps o1 was devised to make use of the process-based reinforcement learning approach, especially since o1 also automatically makes use of chain-of-thought. Whereas generative AI usually requires a user to invoke chain-of-thought, o1 automatically does so. The user seemingly can’t prevent it from happening.