Pareidolia

In psychology, for example, the illusion of seeing faces in everything around you is called Pareidolia.
Pareidolia is a psychological phenomenon, that is to say: a form of illusion in which someone interprets unclear or random observations in such a way that they believe they perceive recognizable things within them. For example: seeing a face shape in the clouds.
The word ‘pareidolia’ comes from Greek ‘para-‘ ("alongside, beyond") and ‘eidolon’ ("image, appearance").
And this is exactly the intention of FAPs, namely that people believe they perceive something, in this case because they desire to see it! The attractiveness of the perception is accentuated by certain lines in the facial appearance.
And our brain is preprogrammed to see certain beautiful aspects beter than others (MAPs).
This 'unconscious neuronal recognition of facial shapes' (MAP) is strengthened in each subsequent birth generation with respect to the human brain. At least, if men and women select each other based on attractive facial patterns (FAP) and genetically reproduce with each other (GAP), causing that trait to return in a reinforced form in the next generation of people.

Here are some examples of pareidolia, in this case the perceived seeing of faces in objects:

Photo: Collage of pareidolia phenomena with estimation or perception-valuation by viewer of the image: gender, age, and feeling.
Plus statistical deviation from average answer; and age-range of the depicted face-in-image.