One of the reasons we idolise superheroes is because they represent the platonic ideal of heroes: they uphold justice, they do good, they save everyone, and they always win out in the end. Right? Well...for the most part. They wouldn't be much good at their jobs if they were letting innocent bystanders get killed by supervillains left and right (cough Man of Steel cough cough), but superheroes aren't perfect. Nope, not even Superman. Overall, superheroes manage to keep the status quo, fighting back any threat that the evils of the universe can throw their way. But it wouldn't be very interesting if you knew that was always going to be the way, right? That's why, sometimes, superheroes fail; they aren't strong enough, they make a mistake, they're in the wrong place at the wrong time. That's the other reason we idolise superheroes so much: sure, they have all that power, but deep down they are - or were, at some point - just regular people like you or me. They can do a lot more than we can, but they're just as prone to mistakes as normal people. It just so happens that when we make mistakes, it usually results in a broken glass or some spilled milk; when superheroes screw up, the consequences are significantly more dire.