>>509080536 (OP)
>Why are most of them animal print designs?
either animals or objects, usually
why? Because people inherently ascribe a character/personality to animals. So for example a knight with a lion on his shield, would represent courage - and everyone would understand this without needing to be told so. An eagle was understood as the king of heavens (religious connotations). A dragon could be considered a dangerous and unpredictable character.
So the simple answer is: that it's simpler and easier to communicate ideas this way.
Of course there's also coats of arms that have people displayed on them - but this defeats the point. Why would a person (who is already a symbol by himself) carry another image of a person? This communicates nothing