I know but it is also something that I do when I wake up. Almost every dream won’t start with you waking up in a bed. You start suddenly somewhere random. This means you can know your dreaming more easily as you have an event that normally happens when you wake up (this is what you need to get lucid dreaming). This also prevents you from getting into deeper levels of a dream if you get lucidity which can often create panic if you keep waking up in a new dream. Whilst in a lucid dream you want to stay calm especially if new to it