The point is to establish a habit such that you end up repeating this habit even when you're dreaming. Often you won't realize you're dreaming when you do this while sleeping, but sometimes you will. This lucidity sometimes doesn't last long, but duration will get longer and frequency increases with practice.
1: These are just regular dreams in which you dream about that you are lucid dreaming. Your awake consciousness is not actually present, your memory is as suspended as it is in regular dreams, you don’t notice flaws in the dream reality and it feels distinctly like regular dreams (like a “bystander”) as opposed to the self awareness feeling in lucid dreams. See https://youtu.be/fqWikLRVby8?si=J0E2BpxO4ff4mam4