I'm the opposite, in my mind it's almost like a CAD program mixed with Photoshop and I have complete control over building and visualizing anything. I can imagine building a lego set piece by piece and how each component looks, feels, slots together with others, etc. I can rotate it all around and imagine sides that aren't visible. I can change the colors and the textures and imagine any kind of lighting. As a kid I would just imagine playing with toys I saw on TV.