Over generalization, mostly.
Early, consistent, socialization makes a big difference.
I've found my fosters (and foster failures) to become the most likely to seek out attention and companionship.
Discussion
See, my girl allegedly didn’t get manners from her mother and I was told this is why she’s so nuts. Her mom abandoned her early… which is why she’s kinda clingy.
Could be.
My most recent addition was abandoned at about two weeks.
(We think. His eyes weren't fully open yet. Had to bottle feed him for quite awhile)
He's my shoulder cat now, but enjoys terrorizing my canines until they drag him around and make a pile of slobber out of him... While he's purring.