For a while, weight-loss injections were the miracle everyone talked about. People lost more weight than they ever had on their own, and for a year or so that was the whole story. Then the story flipped. Now the talk is about what people look like afterwards: faces gone hollow, skin that hangs, a look that says someone has been ill rather than someone who got healthy. You’ve probably seen the photos. They’re the reason people ask me whether the whole thing is a mistake.