Bruises Build Character
My brother and I were once discussing movies we love and turned to the subject of Raiders of the Lost Ark, casually getting into why Indiana Jones was so appealing (aside from the innate charisma of Harrison Ford, of course), and I suggested one reason was the fact that Ford played Jones as a plausibly human hero who actually got hurt. Action films often have the hero surviving things that would kill real people—not only survive them, but walk away unscathed. You see thing like people being shot and still being able to fight on. I referred to Indiana Jones as Johnny Take-a-Beating, and that’s become shorthand between us for a protagonist who actually suffers when the plot hurts them.
I’m currently reading a sci-fi novel whose main character is basically indestructible. There are plot reasons for this having to do with their nature and the technology surrounding them, but just because you can come up with a reason to make your main character a tiny god in your fictional universe doesn’t make that a good writing decision. It’s always lazy writing.
Lazy, Lazy for Loving You
It’s always tempting to make your protagonist indestructible. One reason is it streamlines your storytelling, because no matter what kind of pickle you place them in, they can break free. Another reason is the simple fact that having your main character kick ass all over the place is thrilling, for a time; you can set them up against all sorts of strawmen and comically evil characters and it’s kind of fun as a reader to imagine having the power to instantly master any situation through insane violence that would kill any normal person.
The trick is, if you set your character up as indestructible, it should be leading to a fall. Strip them of their power, remove their technological crutches, and have a plot reason for it all. Not only is having a previously super-powered character suddenly vulnerable kind of thrilling, it can turn all the dumb tractionless violence of the early story into set up for the real payoff.
Otherwise, all you have is a boring character who can’t be harmed. If you can’t be harmed, nothing means anything. It’s like revealing that the entire book has been a dream, so joke’s on you if you thought any of it had consequences.
Plus, I hate reading about people who can run and jump and fight without having to sit down and rest all the time. It’s kind of virtually exhausting.