Of course an LLM does have a latent concept of its own confidence that is internally consistent, and is perfectly able to articulate it, the author just chose the worst possible way to ask. Using a 0-100 scale for anything is a bad idea with both LLMs and people. Instead of rating it 0-100, split your problem into many dimensions/axes and give each a small and meaningful enum or just a less granular numerical scale (ideally just a binary choice). Then apply weighted scoring to the result. You'll be surprised how much better it becomes at meaningfully expressing its confidence this way.
YouTube removed the 1-5 scale for the same reason, people have no idea what to do with it.
YouTube removed the 1-5 scale for the same reason, people have no idea what to do with it.