[bethekidyouwant]

I can also only experience true visualizations when falling asleep or dreaming. I concluded that being awake (correctly?) suppresses vivid visuals and some people when awake simply do not have this (mal?)adaptation.

[kakokiyrvoooo]

https://en.m.wikipedia.org/wiki/Hypnagogia

[drcongo]

I think you're probably right, though sometimes when this happens I feel very awake indeed.