I'm not going to ruin IT for you but when people complain about its ending they are complaining about one particular scene near the end. The end minus that scene is great, it's that scene that ruins it. It's so infamous and hated that all you have to do is say that scene from a Stephen King and they know your talking about IT. If you don't know it already you will when you get there. There will be zero doubt in your mind that its the scene we all hate once you read it. Otherwise ITs ending is good. What King gets ragged on a lot is that his endings drag on way too long or his Dark Tower ending which I think is brilliant but many hate.