Lee sin nerfed again?

Why is lee sin getting nerfed constantly, you cant even play him damage anymore, and he isn't that reliable unless you have a solid team and good communication with everyone. They keep nerfing him even though overall he is only decent mid game now and falls of crazy hard late game. Love this character but lately the nerfs have been completely uncalled for, there are so many other champions that have a broken skill set and game play yet lee keeps getting nerfed. I don't understand