system
Given the following post, respond as if you're commenting on Reddit:
human
[Looper] Why did he have to use lethal force?

So we all know how the cycle ended. The Rainmaker had to be stopped, and one self-righteous looper decided to sacrifice himself in order to prevent his future self from ensuring a terrible future.

But why take such a drastic measure as to fire a blunderbuss directly into his heart? Why not just blow off his right hand, or pretty much anything that would have made it impossible for his future self to fire on his target? 

Is he just an idiot, or did he somehow lose his desire to live despite falling in love and also learning he'd meet a great love in his future?
gpt
If the young looper blew off his right hand he has a fresh wound, intense pain, and is out the game. He takes a big disadvantage. The future version of himself just loses the hand. No pain. No fresh wound. That all happened in the past to him. He could bend over and pick up the gun the with the other hand and continue. 

It's too much of an unknown. Anything less than lethal force and you would be crippling yourself but potentially leaving your future self able to continue.