Firstly, the protagonist is weak, like really really weak. He isn't emotionally weak nor is he someone who isn't confident in himself. In the early chapters, you'd see him struggle because he was a normal person who was thrusted into a survival of the fittest type of world. That isn't something one can just brush off and be okay in just a day. I

 wish to create a realistic protagonist with his own weakness and strength. That goes for the other characters as well.