They're just not accurate enough. For example, Gilmore Girlsis not 'a heartwarming tale of a mother and daughter's relationship', it's an exposé of the two whiniest people on earth continuously enabling each other until the viewer cracks and microwaves themself to death.
Netflix should hire me to compose their description sections. I'd absolutely nail it. I've seen everything and I have no qualms whatsoever in shitting over any movie, documentary or television show.
Here is a sample of my work. Netflix *holds fake phone up to ear* call me!
