I don't know if everyone has had this experience, but when dreaming at night, everything seems especially vivid and memorable. Yet, as soon as you wake up, although you clearly remember having been in a dream, you can never recall the actual scenes within it.
Li Fan found himself in just such a situation, of course, remembering the task the system had assigned him to take out the Italian cannon was crystal clear. That merit couldn't be claimed by anyone else, and it's time to talk about a raise. What Li Fan couldn't remember were the landscapes he envisioned while crossing 'the gate'.
'The gate,' or rather, the act of crossing spatial boundaries and physical laws, from appearing at one point in the universe to another without physically walking there, nor traveling by spaceship, nor even folding the universe like a piece of paper so the two points touch. Thus, Li Fan could only describe it as 'there was a door, and by stepping through, you arrive.'