That it is a cartoon series rather than live action.
That it represents real people and values.
That it regularly parodies and 'pokes fun' at big icons (for example. at religion, politics, history, pop culture).
The style of Matt Groening's animation.
That it has a moral conscience.
The likability of the characters.
The complexity of the characters.
That celebrities guest star (guest voice) on the show.
The time of day it is on.
I do not like The Simpsons.
I have not watched The Simpsons.
That it's random without being obvious about it