I was jailbroken when iOS 7 was first released. I never saw a compelling reason to upgrade. I don't care for the GUI in iOS 7 (way too much white). And I have almost everything iOS 7 has either with a tweak or an app.
Now, even though I could update and jailbreak again I would have to spend a considerable amount of time uupdating my tweaks and finding new ones to replace those that aren't working.
iOS 7 is not worth that effort to me. Everything is the way I want it and it all works. Not going to mess with it.