Comment by Etheryte

I think motivation really is the key term here. Magnus is a five-time world chess champion, in a complete league of his own even when everyone else was literally only prepping to defeat him. He held the world champion title for ten years and eventually just declined to defend it. And that's relatable, if you're at the absolute top for ten years and no one manages to put a dent to it, what else is there? I think most people would look for new challenges and ways to fulfill themselves after that.