A personality is a collection of behaviors evolved for the autonomic maintenance of a complex system.
Everyone is a huge weirdo.
A personality's job is to conjure the specific kind of weirdo necessary to operate the machinery that hosts it: the physical apparatus, a shell in want of a very specific ghost.
Easiest to successfully individuate, i.e. develop a sense of self, by not repressing the weird parts.
Keeping the personality running cleanly and comfortably is its own kind of maintenance.
Which, obviously, means that personalities are stacked. ;) Turtles all the way down.
(see: "congruence", "growing blind")