In depth how do forced perspectives Work?

To understand this effect, we need to explore how our eyes interpret depth in 2d

We subconsciously perceive scale and depth in flat photos by making a number of assumptions. First there’s ‘occlusion’: the assumption when one object partially obscures another – like our foreground figure here in front of the car (blended using a layer mask) – then the obscured object must be further away. Second, there’s ‘relative height’ – here we assume objects that are further away have higher bases, hence the platform we use to raise the car. Third there’s ‘familiar size’, an assumption based on past knowledge of the objects in the frame – we know what size cars should be. By exploiting these assumptions, we can trick the eye.