Isso foi explicado em uma série de entrevistas com o diretor do filme; Rian Johnson:
Por que eles não podem simplesmente transmiti-los ao espaço / ao mar ?
"But I also thought of doing a scene where he (Daniels) says that he’s been complaining to his bosses that this is a stupid system and that they need to find another way. But at the end of the day, it didn’t end up making the cut. The one other thing, and we actually had a line that we cut out in the diner scene, is the fact that the time travel device is not adjustable. That fact that it is set to an exact time and you can’t change when or where it sends you back to. And maybe I should have left that piece of information in the diner scene. But it was part of this longer discussion that Bruce and Joe had that we ended up snipping out to get to the heart of that scene.”
Como a localização + hora são fixos, eles não podem simplesmente transmiti-los ao espaço, nem podem enviá-los para o passado obscuro e distante
Por que eles não criam um dispositivo de assassinato? no local fixo ?
“People in the future, all they know about time travel is to be afraid of it. So they’re trying to keep it as tight as possible. So the initial reason they set it up this way was to keep the causality loop as tight as possible,” Johnson said. Because, for example, if someone else kills your older self and you have to exist with your own murderer for 30 years, what’s stopping you for murdering them or doing something to screw everything else up? ”Every bit of evidence is gone from that loop when you kill yourself,” he said.
A resposta curta é que o plano deles garante que a vítima está realmente morta e cria um loop temporal fechado . Qualquer método automatizado não leva em consideração nenhum acidente nem o fato de que nenhum método de execução automática seja completamente infalível.