Something that ChatGPT has is the tool to create 'custom GPT' (custom assistants).
Basically it's an interface to help create custom prompts for people who need help with it. It's not just a "here's what I need my assistant to do". it's an actual chat on the left where you can give it feedback and on the right you can try out each version of the prompt as it changes it.
While I personally only use this maybe once a month or less (because I rarely make custom assistants. I only need a couple), it is really nice to use.
I honestly already thought there was a kf about this, but couldn't find one.
I think this feature is very important for people who may not know the best practices of prompt 'engineering' or know what to and not include.
For the people who aren't super familiar with llm's, this feature is very important to make them useful I think.
Personally I also really like it because it allows you to quickly change, and right away test new custom prompts.
There's many videos on youtube showing how the interface works: https://www.youtube.com/results?search_query=gpt+builder