Shelf lives of cartoons

No.119521793 ViewReplyOriginalReport
What do you consider the standard shelf-life of a cartoon? I.e. how long it remains good.

I feel like somewhere between 6-9 years. I think South Park started going downhill in season 10, I think Family Guy started going downhill around seasons 7-10, I think Rick and Morty is going downhill now which is 7 years after it premiered, and I think The Simpsons started going downhill during Season 9 (though I enjoy the Scully years).